Table of contents

The 2021 2nd International Conference on Geology, Mapping and Remote Sensing (ICGMRS 2021) was be held virtually online on April 23-25, 2021 due to the precaution taken to minimizing the COVID-19 risk. The safety and well-being of all conference participants was our first and top priority, while we strived to offer many scholars and researchers this long-awaited conference to conduct academic exchanges with their peers.

ICGMRS 2021 is to bring together innovative academics and industrial experts in the field of geology, mapping and remote sensing to a common conference. The primary goal of the conference is to promote research and developmental activities in geology, mapping and remote sensing and another goal is to promote scientific information interchange between researchers, developers, engineers, students, and practitioners working all around the world.

The COVID-19 virus has made our life very challenging, but we want to reiterate that there are no barriers to science, as we continue to do our research works via modern technical means. The ICGMRS 2021 has selected Zoom as the virtual platform. Each presenter will be given a 15-minute talk and followed by a short discussion afterward. Before the conference, all of the authors were encouraged to submit a video as a backup in case of unexpected technical problems. There were 140 individuals who attended this on-line conference, represented many countries including China, Canada, South Korea, Singapore and UK.

During the conference, we invited three professors as our keynote speakers. A. Prof. Chao Chen, from Zhejiang Ocean University, performed a speech: Spatio-temporal pattern evolution of coastlines for archipelagic regions. His research area is Marine Environment Remote Sensing. And then we had A. Prof. Heng Dong, from Wuhan University of Technology. He delivered a speech: Estimation of Global Terrestrial Gross Primary Productivity based on Solar-Induced Chlorophyll Fluorescence. In this study, after analyzing the fluorescence emission mechanism at different spatial scales, and the GPP-SIF empirical linear estimation model, some factors affecting the photosynthetic capacity of the vegetation and the canopy SIF emission were introduced to construct a new GPP estimation method. Lastly, we were glad to invite A. Prof. Xuemin Xing, from Changsha University of Science & Technology as our finale keynote speakers. She shared a speech: Measuring subsidence over soft clay highway based on a novel time-series InSAR deformation model: with emphasis on rheological properties and seasonal factors. Their insightful speeches had triggered heated discussion of the conference. Every participant praised this conference for disseminating useful and insightful knowledge.

The proceedings are a compilation of the accepted papers and represent an interesting outcome of the conference. Topics include but are not limited to the following areas: Geography & Geology, Surveying & Mapping, Remote Sensing, Application of Remote Sensing Technology and other related topics. All the papers have been through rigorous review and process to meet the requirements of International publication standard.

We would like to acknowledge all of those who supported ICGMRS 2021. The help and contribution of each individual and institution was instrumental in the success of the conference. In particular, we would like to thank the organizing committee for its valuable inputs in shaping the conference program and reviewing the submitted papers.

The Committee of ICGMRS 2021

Committee member, Conference Chair, Program Committees, Technical Program Committees and this titles are available in this pdf.

All papers published in this volume of IOP Conference Series: Earth and Environmental Science have been peer reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

• Type of peer review: Double-blind

• Conference submission management system: AI Scholar System

• Number of submissions received: 301

• Number of submissions sent for review: 287

• Number of submissions accepted: 169

• Acceptance Rate (Number of Submissions Accepted / Number of Submissions Received X 100): 56.1%

• Average number of reviews per paper: 2

• Total number of reviewers involved: 90

• Any additional info on review process:

• Step 1. Each of selected paper will be reviewed by two/three professional experts in the related subject area.

• Step 2. Review Reports received from the experts will be judged by one of the editors either Review Reports are logical or not?

• Step 3. If not logical, then editor can assign new reviewer or can also judge at his/her own.

• Step 4. If logical, then Review Reports will be sent to authors to modify the manuscript accordingly.

• Step 5. Authors will be required to revise their papers according to the points raised.

• Step 6. Revised version will then be evaluated by the editor for the incorporation of the points raised by the reviewers.

• Step 7. Then the editor will send the revised manuscript to the reviewers again for re-evaluation.

• Step 8. If the reviewers approve the revise version of the manuscript, then will be accepted for publication.

• What criteria were considered when assessing the articles:

A. Style and Organization:

1. Is the paper clearly presented and well organized?

2. Is the English satisfactory?

3. Is the title appropriate?

4. Are the figures, tables, and their captions clear?

5. Are the references to related work adequate?

B. Scientific Quality

1. Contains significant contributions to the advancement of the subject.

2. Sound, original, and of interest.

3. Does not add to knowledge of the subject.

4. Contains fundamental errors.

• Contact person for queries:

Xuexia Ye

publication@keoaeic.org

AEIC Academic Exchange Information Centre

Based on the relationship between soil strength index and water content, the stability of tunnel portal slope during tunnel excavation in water rich soft soil area is analyzed according to the change of soil water content under different working conditions during tunnel construction. The results show that the strength index of soil decreases in inverse proportion with the increase of saturation. Reasonable excavation speed or effective dewatering measures are conducive to the self stability of the open cut slope. When the duration of heavy rainfall does not exceed 2 h, the slope is in a stable state; when the duration reaches 10 h, the slope enters the limit equilibrium state; when the duration reaches 18 h, the slope enters the failure state.

With the accelerating urbanization in China and the constant development of underground space, shield tunnels have been extensively applied to underground roads in central urban areas. However, the central areas are featured with complex surroundings, such as numerous subways, bridge pile foundations, basements, pipelines, and other structures and buildings. Therefore, it will be an unavoidable engineering difficulty for the construction of shield tunnel in the central urban area to cross at a close range buildings (structures) such as existing tunnels, underground pipelines, underground passages and basements. At present, there are remarkable research results for the crossing of subway shield tunnel with an outside diameter of 6.0 m, and rich research results for the crossing of shield tunnel with an outside diameter of 10-14 m. However, there are relatively few studies on the shield tunnel with an outer diameter of 15 m and above crossing existing buildings (structures). Based on Shanghai Beiheng super-large-diameter shield tunnel (outside diameter 15.0 m), the Midas_GTS finite element analysis software was used herein to study the relation between the underpassing clearance distance h and the peak settlement of existing metro tunnel S. The optimal clearance distance of the super-large-diameter shield tunnel underpassing the existing metro tunnel in the soft soil area h was drawn to be 7.0∼8.0 m. Through analysis, it was found that the ground loss rate ρ and the tunnel peak settlement S of the existing tunnel was linear, with the slope = 2.795 > 1. It proved that the tunnel peak settlement S of the existing tunnel was significantly influenced by the ground loss rate ρ. Therefore, it' s quite reasonable to take the ground loss rate ρ as the evaluation indicator and control requirement for crossing construction.

Based on the concrete engineering support of the tunnel anchor of the Dadu River Bridge on the Sichuan-Tibet Railway, the geological background of broken rock mass, extremely developed joints and fissures, and poor self-stability of surrounding rock within the range of side anchors in Chengdu, a three-dimensional elastoplastic numerical calculation method is used. The current engineering geological conditions and the tunnel anchor design plan are to establish a three-dimensional fine numerical simulation model of the Chengdu side tunnel anchor that comprehensively considers rock mass unloading, stratum classification, and anchor tunnel excavation and support structure. The "excavation-support" process in each construction footage is simulated to realize the three-dimensional calculation of the dynamic construction and support of anchor tunnels, and to study the surrounding rock deformation, stress and plastic zone distribution changes during the excavation process. Comprehensive analysis found that the deformation of surrounding rock during excavation shows that it develops toward the empty surface, and the displacement distribution is obviously affected by the distribution of ground stress and rock formation. The greater the buried depth, the greater the deformation of the surrounding rock.

In view of the obvious deformation characteristics of shallow buried soft surrounding rock tunnels affected by excavation disturbance, this article takes a Tunnel as the engineering background and combines the geological conditions of the tunnel to carry out on-site monitoring and analysis of surrounding rock deformation after tunnel excavation. The deformation after excavation has the characteristics of fast deformation speed, long duration and large deformation. In addition, the excavation position and step have an important influence on the settlement of the vault and the convergence of the surrounding rock. The settlement of the vault and the convergence of the surrounding rock caused by the excavation of the upper and middle steps account for 61.16% and 63.34% of the total deformation respectively. Through the analysis of large deformation and collapse phenomenon, it is known that the large deformation mechanism in the cave mainly includes soft rock plastic flow and progressive loosening expansion. The soft rock plastic flow caused phenomena such as side wall bulging, top pressure and steel arch distortion, and the progressive loosening and expansion caused the collapse of the tunnel face and surface cracks. Finally, according to the principles of the New Austrian Method, temporary support (transverse bracing + vertical bracing) + grouting anchor pipe + spray-mixing coordinated support was used to construct the pipe shed at the same time, and the support was optimized, the leading small conduit was encrypted, and added Measures such as temporary invert and lock-foot anchor pipe have successfully dealt with the large deformation section of the collapse, and the treatment effect is good, which can provide reference and reference for similar projects.

This article analyzes the relevant content of the safety design of civil engineering structures. This paper studies the common problems in the safety design of civil engineering structures, including design methods to be optimized, relatively low training efforts, relatively poor innovation capabilities, more construction safety hazards, unreasonable internal force combination design, and low safety supervision. The author studied how to optimize structural design methods, how to strengthen personnel training, how to deal with system innovation, how to strictly control building conditions, how to optimize the design of internal forces, and how to strengthen safety supervision. The purpose of this article is to improve the level of civil engineering structural design and improve the construction quality of construction projects.

This paper is based on a typical project in Shenyang Shangshenbei Block Project, using Midas software to analyze the temperature stress of the basement concrete structure and the temperature stress changes of various parts of the basement, combining the conditions and characteristics of the concrete structure cracks, and putting forward optimization suggestions and effective resistance. Cracking measures, through the implementation of measures, effectively reduced the occurrence of cracks and ensured the stability of the structure.

Luzi Yuan lead and zinc polymetallic deposit is located at Zhenkang anticlinorium which is on the south section of baoshan block. Four main mineralized zones are included in this area, namely I, II, III and V. Among them, II-V₁, II-V₃ and III-V₅ in NO II mineralized zone contain the main orebodies. Througn research the author believes that the deposit shows obvious mineralization alteration zonality from deep to superficial part. It appears that the orebodies are controlled by faulted structure and occur as banded, stratified, stratoid and veined in form along faut fractured zone in the trend of northeast. The analysis and summary of characteristics of mineralization and associated elemengts in this area in this paper provided basis for future prospecting works.

This paper studies the reservoir sedimentary system of an oilfield, grasps the origin and characteristics of sand development in narrow and small river channels, and uses the method of sandstone facies determination to track and predict sand bodies, and establishes the continuous distribution mode of channel sand bodies. On this basis, combined with the dynamic monitoring data, the type and potential of remaining oil in the oilfield are analyzed by using the dynamic analysis method, and five potential tapping directions centered on the channel sand body are determined. The practice shows that the remaining oil analysis based on the anatomy of single sand body should be paid more attention to in the exploration of potential in high water cut period. Combined with various technical means such as reinjection, encryption and orientation, the injection production relationship of single sand body should be improved and the field application has achieved good results.

The leucogranite-hosted uranium deposit in Namibia is a well-known intrusive uranium deposit in the world. In this paper, a systematic study of Sr-Nd isotopes has been carried out on uranium mineralized leucogranites in the Gaudeanmus area, Namibia. The results show that uranium bearing leucogranites were formed in the post-orogenic extensional environment, the εNd(t) values of the rock are from -13.5 to -17.4, with the initial ⁸⁷Sr/⁸⁶Sr ratios of 0.73035 ∼ 0.79345; and the ages of two-stage Nd model are between 2.32 ∼ 2.63 Ga. The Sr-Nd isotopic geochemical results of the pre-Damara basement, Damara sequence and uraniferous leucogranites indicate that the contribution of uranium rich pre-Damara basement to the ore-forming materials is dominant during the main metallogenic epoch of magmatic crystallization differentiation, while the extra uranium mineralization at the later hydrothermal stage may be from the primary uranium minerals such as uranite and coffinite.

Wuerxun depression is one of the main oil-bearing depressions in the middle of the Hailar District Basin with high exploration degree. With the deepening of exploration degree, the pore structure and distribution law of tight reservoir in trough are not clear. In this paper, through the combination of quantitative and qualitative, micro and macro, following the idea of "phenomenon characterization, essence exploration, law summary", the diagenesis analysis and diagenetic evolution of tight reservoirs are studied to find areas with relatively good reservoir properties in the depression, which provides theoretical basis for tight reservoir exploration. Diagenesis controls the formation, evolution and distribution of the reservoir. The diagenesis of the reservoir in this area mainly includes compaction, cementation and dissolution, thus forming five kinds of secondary dissolution pores (intergranular dissolution pore, feldspar and debris dissolution pore, mold pore, interstitial dissolution pore and dissolution fracture). Vertically, the physical properties of the reservoir are generally poor, but the reservoir is well developed locally. The reservoir is well developed at 1300-1900m and 2300-2700m in Wuerxun depression.

In order to improve the success rate of oil and gas exploration and further study the impact of tight sandstone cements on reservoirs, this paper uses a large number of rock thin sections, scanning electron microscopy, and physical property analysis to analyze the cements of the Chang 6 reservoir in the Panke area, southern Ordos Basin. Features have been studied in depth. The results show that the cements in the study area mainly include: authigenic cements such as illite and chlorite, carbonate cements such as iron calcite and iron dolomite, and siliceous cements. As the depth of the stratum increases and the temperature rises, the content of illite gradually increases; the main distribution area of chlorite cement is shallower than that of illite; with the increase of buried depth, the content of carbonate cement has a increase trend ; The content of siliceous cement in the deeper stratum is higher than that in the shallow layer.

The alteration zone around pegmatites can be used as a direct tool to trace the property of pegmatite-derived fluids. In the present study, EPMA, LA-ICP-MS, and MC-ICP-MS were used to analyze major elements, trace elements and boron isotope compositions of tourmaline from Qinghe barren pegmatite, NW China. Most tourmalines from the pegmatite are schorl, while the remaining tourmalines from the pegmatite, the contact zone, the altered wall rock and the unaltered wall rock are dravite. All tourmalines follow the exchange vector (Fe + Mg) (Al + X_vac)₋₁, indicating enriched Fe and Mg. The Fe³⁺Al₋₁ exchange vector and increase of V/Sc in the late stage suggest sudden destruction of the pegmatite system. The δ¹¹B indicates that a small scale fluid exsolution occurred in the late stage. Compared with other fertile pegmatites around the world, Qinghe pegmatite has the most negative δ¹¹B and lower Li content, indicating that both the source and evolution process have an impact thereon.

The current research on the mechanism of blasting compaction mainly focuses on how to form a rockfill dam under the action of blasting load, but there is little research on the dynamic response characteristics of soft soil media under blasting. In blasting compaction of deep silt, it is necessary to pay attention to the damage and disturbance effect of explosive explosion on the surrounding soft soil medium, thereby providing new ideas for the study of blasting compaction mechanism of deep silt. With a seawall project in Huizhou as a prototype, based on the blasting similarity theory and through a generalized model and parameter similar design, experimental research on deep silt blasting compaction centrifuge was carried out in a 200g-t centrifuge. The physical and mechanical parameters of the silt soft soil at different positions were acquired through testing before and after the blasting, and property changes of the soft soil medium were analysed under the explosion to speculate disturbance range of the soft soil medium under the explosion effect, and divide the different blasting disturbance areas. The test results provide data support for the optimization of the design parameters of the seawall project, and also provide a useful reference for the study on the blasting compaction mechanism of deep silt and similar engineering practices.

Water is an indirect construction disturbance factor, which has important influence on the stability evaluation and analysis of foundation pit slope engineering. The study is mainly aimed at the deep backfill, the mechanical parameters are not uniform, and the effect of water on its mechanical parameters is great. The mechanical parameters of the backfill under different moisture content were measured by static triaxial shear test. The results show that the cohesion, internal friction angle and shear strength of the backfill are attenuated with the raise of the water content, the cohesion and internal friction angle of the attenuation law showed a linear re-gentle trend, and the shear strength of the decay trend gradually slowed down. The simulation results show that the mechanical parameters of backfill are reduced with the increasing number of saturation-dehydration cycles. The first degree of decay is the most significant, and finally tends to a certain value. The connection between the deterioration coefficient and the cycles follows the negative exponential function, and the mathematical expression of water deterioration was obtained finally. The study analyzes the damage mechanism of water in the construction disturbance, which has some theoretical support for the stability evaluation and disaster mitigation of the foundation pit.

The durability of geopolymer coatings is significantly influenced by water infiltration. In order to reduce the ingress of water, a slag-based geopolymer was modified respectively using methylsilicone oil (MSO) and organic silicon agent (OSO). For the characterization of the surface interaction between geopolymer and liquid, the contact angle, surface energy and critical surface energy of geopolymer were measured by a novel and accurate bubble method. Results show that surface hydrophobic modification of geopolymer is completely achieved by MSO modifier due to the increasing contact angle on the surface of geopolymer and the surface energy of geopolymer decrease to a certain extent. The critical surface energy curve is not only can describe wetting performance of the geopolymer, but also can predict the wetting feature of a specific liquid on the surface of the geopolymer intuitively and quickly.

The sunlight in summer is generally strong in hot summer zone, so the long-lasting shadow is conducive to people's outdoor activities for a long time. Creating a space with "Constant-holistic Shadow" has become an important way to improve the outdoor thermal comfort. However, with special shadowing condition featuring in a varied topography with big vertical height, the sunshine shadowing formation in mountainous urban area is significantly different from that of plain area. Therefore, it is necessary to take the special shadowing conditions into consideration in exploring the influence and relevance on the "Constant-holistic Shadow" construction. This paper analyzed the characteristics of outdoor spatial morphology and shadow forming elements in mountainous urban areas, revealed the correlation between the characteristics and "Constant-holistic Shadow" space, and expounded the main design strategies of "Constant-holistic Shadow" space in mountainous urban areas so as to provide ideas and strategic guidance for more effective construction of "Constant-holistic Shadow" space in mountainous urban areas.

The method of combined hole arrangement on both banks and in the middle of the river was proposed for the test and analysis of the flowing water velocity in contact passages at the bottom of the Wulong River in order to address the insufficient reliability of the existing testing method for the flowing water velocity in the bottom stratum and its failure to truly reflect the data and law of the velocity in the stratum of bottom contact passages in the shield section. Meanwhile, the measurement time of each measuring hole has experienced the fluctuation cycle of the water level, enabling the parameters and law of the flowing water velocity obtained from the test to cover the complete spatial and temporal distribution range. Compared with the existing research, the method has a greatly improved data reliability, guiding the freezing reinforcement construction of bottom contact passages successfully. At the same time, the flow distribution law, velocity range and the law of influence of water fluctuation on the flow velocity revealed in this test can provide reference for related engineering projects in the region.

The cubic compressive and splitting tensile strength of recycled aggregate concrete reinforced with hooked-end steel and macro-polypropylene hybrid fibers (HFRRAC) was investigated through an orthogonal experiment. The results show that the replacement ratio of RCA has little effect on the tension-compression ratio. And the volume percentages of HES fiber are the most significant influencing factor in terms of fibers. The specimens reinforced with fibers fail in a ductile manner and are enhanced in the energy absorption capacity. The proposed prediction models for cubic compressive and splitting tensile strength of HFRRAC are adopted to predict the experimental results and meet the engineering application accurately.

Coupling beam is an important component of seismic structure, the damage of coupling beams can consume earthquake energy, thereby protecting the safety of the structure. In order to ensure that the advantages of steel coupling beams are fully utilized, the joint connection form of steel coupling beams and structures has become the focus of many scholars' research. This paper systematically summarizes the latest research progresses on the connection mode of joint with steel coupling beam, and their advantages and disadvantages are discussed, which provides a reference for engineering application.

The seismic-resistant concrete structure is an important component in the buildings and plays a key role in many countries, like Japan, Philippine and America. Different from traditional ways, the use of precast concrete in those areas is feasible now. Regardless of the progress in the area of precast concrete, the major problem of joint technology persists. This paper aims to review the existing precast concrete structures and some other seismic-resistant concrete structures. It is concluded from this review that the performance of precast concrete is the same as traditional methods and has its benefits in construction and economic aspects.

Sericite schist is an extremely soft rock. Most of the sericite schist residual soil in nature is in an unsaturated state, The matrix suction of the residual soil has a great influence on its strength. In this paper, an unsaturated quadruple consolidation tester and an unsaturated triaxial creep tester are used to carry out one-dimensional and three-axis creep tests on sericite schist residual soil. The test results show that the creep characteristics of the soil sample are obvious. Both the one-dimensional and triaxial tests show obvious three-stage characteristics. At the same time, the influence of the matrix suction and the net vertical stress on the creep characteristics of the soil is comparatively analyzed.

The main function of the pile foundation is to bear the vertical load, but in actual engineering, the pile foundation usually bears combined loads which contain vertical load, lateral load and bending moment. Under combined loads, due to the P-Δ effect, the calculation of the bearing capacity and deformation of the pile foundation is very complicated. The small deformation superposition principle recommended by the current pile foundation codes fails to consider the resistance of the soil around the pile under the combined loads, and it is difficult to accurately evaluate the influence of P-Δ effect on the bearing capacity and deformation of pile foundation. In view of this, this paper firstly starts from the potential energy equation of the pile-soil system and deduces the calculation formula for the horizontal displacement of the pile considering the P-Δ effect, and it is verified in conjunction with related calculation examples. Then the factors affecting the P-Δ effect are discussed in detail, and the results show that the larger the load ratio is, the more obvious the P-Δ effect will be; when the pile top is fixed under the same load condition, the P-Δ effect will be significantly weakened.

In order to explore the influence of groundwater on the surface settlement law of shield construction under mudstone with different weathering degrees, this paper studies the influence of buried depth on surface settlement under different weathered mudstone, and the influence law of groundwater in stratum and different depths of water level on settlement of shield construction using a three-dimensional(3D) numerical model establish by finite element software based on the engineering background of Chengdu Metro Line 18. The results show that: (1) With the increase of buried depth, the range of lateral settlement trough on the surface gradually increases, but the maximum settlement gradually decreases. By analyzing the buried depth and the maximum surface settlement, it is found that the buried depth ratio has a logarithmic relationship with the corresponding maximum surface settlement. (2) The construction settlement increases obviously when there is groundwater in the stratum compared with when there is no groundwater. (3) The depth of water level above the vault and the maximum settlement caused by shield construction basically conform to the linear law. For every 1m increase in the depth of water level above the vault, the maximum settlement value can increase by about 0.43 mm. Compared with the field monitoring data, the calculation results are basically consistent, which shows the reliability of the calculation. This paper aims to provide experience for similar projects.

The integration of underground single structure and retaining structure is a new type of foundation pit support, and its working performance needs to be further studied. The physical model test was carried out on the diaphragm wall structure of "two walls in one" in this paper. The soil settlement and the earth pressure of the outside of the foundation pit and the stress of the integrated supporting structure were analyzed when the excavation depth is different. The analysis showed that the settlement of soil behind the wall gradually increased with the increase of excavation depth of the foundation pit. when it was 1H_e away from the diaphragm wall, the maximum of soil settlement occurred, which was 0.08%H_e(H_e is the maximum excavation depth). With the increase of excavation depth, the state changed from static to active. Under the same condition, the bending moment of the wall increased first and then decreased with the depth. The reverse bending point is near 1.23H_e.

With the increasing demand for mineral resources, the exploration work needs to be strengthened, and the factors affecting the layout of exploration projects need to be further studied. In this paper, the bauxite deposits in the Luoyang Yellow River Basin, Western Henan, are the research objects. According to the geological background and mining characteristics, the influence of tectonism on bauxite mineralization and exploration is comprehensively analyzed. The comprehensive exploration methods (such as geology analysis, drilling engineering, geophysical prospecting, and testing) are used to evaluate the metallogenic prospect of the study area. Through field practice, good prospecting results have been achieved.

Mineralogy is very important in the study of lake, especially in the study of regional and past global change using lake sediments. In the final analysis, mineralogy could be involved in the study of the in-depth mechanism of lake sediments. In this paper, analysis the minerals by XRD in the sediments of Toson lake in the northeast of Qinghai-Tibet Plateau, the results showed that the main minerals in Toson lake were aragonite, calcite, quartz, halite, albite, muscovite, clinochlore and dolomite. And the main categories were detrital minerals and carbonate minerals with obvious reverse correlation. It suggested that Toson lake was mainly situated carbonate sedimentary stage, and the input of carbonate was lacustrine authigenic carbonate.

The Karnaphuli River underwater tunnel in Bangladesh is located at the estuary of the Karnaphuli River and is constructed with a Φ12.12m air-cushioned slurry pressure balance shield machine. The bottom section of the river mainly passes through a dense silty fine sand stratum, of which the standard penetration value and strength are high. When the shield tunneling got into to the sea area, the tail shield was significantly and unevenly deformed, which caused the shield machine to be trapped in the river bottom. Therefore, the characteristics and causes of the deformation of the shield tail during the tunneling boring process were analyzed on this basis. Studies have shown that the deformation of the tail shield was a gradual development process. If there is a slight lack of rigidity of the outer shell and tail shield on the outside of the shield, it tells that the large resistance of the ground caused by the deviation of shield tunneling is the main reason for the deformation. Besides, given the construction characteristics of the underwater shield and the limited working space in the shield machine, a linear rectification tool was designed. By summing up the rectification methods of the hole making in the tail shield, decompression with sand discharge, and incremental launching with loaded, local deformation of the tail shield was realized, so the trapped shield machine was successfully released. Finally, through the excavation experience after the shield restart, it is concluded that within 5cm of the tail shield steel plate deformation, the experience of deformation rebound can be achieved through measures such as sand discharge through radial holes and bentonite injection, which provides a reference for similar engineering projects in the future.

Bamboo is an outstanding, widely used historical green building material that features high strength, economic, and sustainability. The joints in a structure are the important points for resisting the loads. However, the connection of bamboo pole is always the major challenge during the construction. The thin-wall, hollow and other irregularities of this natural material contribute to the challenges of making connection systems. To utilising bamboo in the construction industry, this paper summarises the existing bamboo connection methods including both traditional and modern ones.

In order to support the high-precision and high-quality prefabrication of steel shell concrete immersed tube for Shenzhen-Zhongshan Bridge, this paper analyzes the influence of temperature field produced by concrete hydration heat on the deformation and local stress of steel shell concrete immersed tube considering the influence of strength time-varying, autogenous shrinkage and creep of concrete and casting technology. Then, this paper puts forward the temperature control index of concrete molding based on the control requirements deformation and local stress of immersed tube. The results show that: the hydration heat of concrete is beneficial to the deformation control of steel shell concrete immersed tube, and it has little influence on the final deformation, the molding temperature of concrete should be controlled below 3°C of the ambient temperature to prevent the cracking of steel concrete interface of immersed tube. The research results of this paper have been applied to the control of concrete casting process of steel shell concrete immersed tube for Shenzhen-Zhongshan Bridge, which can make up for the domestic research blank and provide technical reference for similar projects.

High-rise buildings especially super high-rise buildings are booming with the rapid urbanization because the urban population increases dramatically. For the sustainable development of super high-rise buildings, construction safety is an important issue. Since tower cranes are widely applied on the construction of super high-rise buildings as the lifting and transportation equipment, their safety is closely related to the safety of construction sites. In this study, a reasonable safety evaluation system with clear input and output indicators was first established. Then, the input index was quantified, and their weights were determined according to their importance which were ranked based on the fourth-class division method of safety grade. Subsequently, the neural network model was developed. 90 tower crane accidents were evaluated quantitatively which provided the data to train and verify the model. The results show that prediction of neural network model is reliable. The trained neural network model is capable to predict the tower crane risks of high-rise buildings, which can be helpful to the construction safety management.

Based on the physical phenomenon of the fiber reinforced polymer material after the erosion of the liquid medium, the erosion law of the liquid medium on the FRP is analyzed. And considering the anisotropy of the FRP material, a FRP point source erosion depth model based on Fick's law is proposed. Taking the glass fiber reinforced polymer (GFRP) in alkali solution as an example, we carried out GFRP corrosion and aging test in alkaline solution, and the erosion depth of GFRP specimens was measured at 30, 90, 180, 360 and 720 days, respectively. At the same time, the water absorption rate of GFRP was used to calculate the erosion diffusion coefficient of solution medium. Through the comparison between the experimental value of erosion depth and the calculated value of erosion depth model, the error between the experimental data and the calculated data is within 10%, and the overall regularity is consistent. It shows that the erosion depth model of liquid medium proposed in this paper is reasonable and has high accuracy.

In this paper, ordinary portland cement, aerogel powder, graphite modified polystyrene (EPS) particles, foaming agent and additives were used to successfully prepare ultra-light insulation foamed cement-based composite with dry density of 120 kg/m³. The effects of graphite modified EPS particles on its density, mechanical properties and thermal conductivity were studied. The research results show that: When adding graphite modified EPS particles with volume content of 30%, the foam concrete has the best performance, with compressive strength of 0.25 MPa and thermal conductivity of 0.0326 W/(m·K); It shows that the compressive strength can be maximized and the thermal conductivity can be minimized when the filling amount of graphite modified EPS particles and the pore structure of foamed cement-based materials reach the best composite ratio.

Steel-concrete structures are widely used because of their large space and strong plasticity, but the long construction period, complex splicing process and other factors will make the main body of the structure directly exposed to solar radiation, resulting in temperature changes on the surface of steel structure and concrete structure. In order to obtain the stress changes of steel-concrete structures under solar radiation, two kinds of steel-concrete structures with different support forms were simulated. Under three temperature gradients, the thermal behavior and mechanical properties of two kinds of steel-concrete structures composed of upper steel roof and lower concrete support were analyzed. The results show that there is a linear relationship between the thermal behavior and stress response of steel-concrete structure and the daily temperature difference caused by solar radiation. Under the action of thermal effect, the stress difference between the lower steel frame of the full support structure and the lower steel frame of the support structure on both sides is about 10.7%.

Under the background of urbanization and the improvement of living standard, building energy consumption is increasing day by day and energy saving and consumption reduction in construction industry is imminent. As a new type of energy-saving healthy and livable building, passive building will inevitably become the development trend of future buildings. Based on the factors that affect the energy consumption of passive buildings in hot summer and cold winter areas, this paper finds out the main influencing indexes, calculates the accurate index weight by AHP and corrects it by entropy weight method in order to be more objective. Finally, the method is applied to an example and relevant suggestions are put forward based on the research results and the examples.

During the 1995 Kobe earthquake, the Daikai subway station witnessed serious collapse, which attracted the attention of people to the earthquake damage response of the subway structure. To study the earthquake failure mechanism of a subway station structure, two comparative dynamic centrifuge tests were performed. During the centrifuge tests, many important physical quantities cannot be directly monitored with appropriate instruments due to many limitations, such as extremely small model structures, extremely high collection frequency and complex centrifugal environment. To study the earthquake failure mechanism of a subway station structure in depth, an extended analysis of model tests was performed by means of numerical model. Finally, the earthquake failure mechanism was summarized in detail based on the numerical analysis.

This study aims to evaluate the effects of catalyst (MnO₂) and coagulant (Li₂CO₃) on the properties of aerated concrete consist of Portland cement, aluminate cement, and grade I fly ash by the chemical foaming method. In this experimental investigation, the compressive strength and thermal conductivity of aerated concrete were tested by more than 70 aerated concrete specimens with catalyst ranging from 0 to 2.0% and coagulant ranging from 0 to 4.0%. The results indicated that catalyst had a positive effect on the foaming efficiency when the foaming agent percentage is 4%. The positive impact reaches the peak when the catalyst percentage on 0.4%. Outcomes show that the compressive strength of aerated concrete decreases slowly with the increase of coagulant content. Still, the thermal conductivity decreases significantly due to the pore size of the foam increases. The study also reveals that the coagulant effect on ordinary Portland cement concrete setting is not apparent.

During the blasting construction, the problem of building vibration caused by blasting cannot be ignored. Therefore, this paper uses the measured blasting seismic wave of a shaft in Qingdao Metro as the input parameter to conduct numerical simulation to research the influence of blasting vibration of shaft on brick concrete bulidings. The results show that The Z-direction vibration velocity has obvious local amplification on the roof, and the amplification factor is 1.4-1.9 relative to the top floor. The magnification factor on the backward side is smaller than the magnification factor on the frontward side, and the elevation magnification effect gradually weakens as the elevation difference increases. HHT (Hilbert-Huang Transform) method is used to analyze blasting seismic wave signals, when the blasting seismic wave propagates from the first floor of the brick concrete buliding to the roof, the energy is reduced by about 67%-80%. The frequency band of 0-30 Hz is the main range of blasting energy distribution in brick concrete buildings, and attention should be paid to resonance phenomenon.

To investigate the effect of water-cement ratio and stone powder admixture on the plastic shrinkage performance of self-consolidated concrete by measuring the shrinkage deformation within 24 hours after casting through non-contact shrinkage test. The test shows that the larger the water-cement ratio and the higher the stone powder admixture, the larger the early-age shrinkage value; the early-age shrinkage growth rate is mainly affected by the water-cement ratio, and the early-age shrinkage growth rate tends to level off later for small water-cement ratio; the effect of stone powder admixture on different water-cement ratios is slightly different, and the increase effect of stone powder admixture on early-age shrinkage is more obvious under the high water-cement ratio condition.

In order to study the vacuum preloading settlement characteristics of Hengli Island soft strata, the monitoring data of the vacuum preloading area are analyzed, and the hyperbolic method and the three-points method are used to predict the final settlement. The results show that the variation trend of settlement, vacuum degree and water level has a high consistency. The larger the calculated data span, the larger the calculated result. The three-points method is closer to the measured value than the hyperbolic method, the ratio of the three-points method to the measured value was 94%∼110%, and the latter 110%∼120%. However, the three-points method is sensitive to settlement saltation, and the calculation result error will be large if the calculated data span the saltation region, while the hyperbolic method is not sensitive to settlement saltation. According to the settlement rate and predicted settlement, the unloading time is earlier than the actual unloading time, which provides a reference for the reasonable evaluation of the unloading time and the reduction of the low-efficiency preloading time.

With the rapid development of urbanization in China, the old urban buildings in many cities are facing the problem of weakening function. There are broad prospects for floor-adding renovation and expansion of in-service houses. In this paper, based on the background of the actual project, the direct floor-adding scheme is adopted to design the existing buildings after the reliability evaluation. The key point of the floor-adding reconstruction and expansion is whether the new part can be reliably connected with the old structure. In view of this weak link, this paper makes a further study on the seismic performance of new frame column members with different anchorage depth, which provides a certain guiding significance for the design and construction of story-adding reconstruction and expansion.

The foam concrete test blocks with different design densities were prepared. Different dosages of hydroxypropyl methylcellulose on the quasi-static energy absorption characteristics of foam concrete were studied through comparative experiments. The results show that the foam nominal load-displacement curve can be divided into three stages: elastic compression stage, plateau stage, and a densification stage. The higher the density of the foam concrete, the higher the initial peak load, the more outstanding the load fluctuation, and the worse the protective performance. The smaller the density, the longer the compression platform stage. 0.06% of HPMC improves the energy absorption characteristics of foam concrete with different densities the most, and the smaller the density, the greater the improvement ratio.

Bridge is an indispensable infrastructure since ancient times, and the structure types of bridge are divided into beam type, arch type, cable-stayed bridge and suspension bridge. Bridges need to be safe and strong for a long time. Architects are always looking for ways to make Bridges last longer. This paper analyzes the sustainability of bridges. The way to extend the service life of the bridge will be discussed.

As the most basic structural unit of shield tunnel, the segment will cause tunnel quality problems and ultimately affect the service life of the tunnel. Based on the actual project, this paper takes the segmental cracking phenomenon in the a large diameter shield tunnel as the research object, and analyzes the influence of the three protruding bosses of the cracked segment itself and the adjacent small ring on the segment cracking. Mechanical analysis, and finite element simulation of the force form of the tube under the unevenness of the boss. Through analysis, it is found that the three bosses of the cracked tube itself have little effect on the cracking of the segment, and the unevenness of the annular seam is the main cause of cracking of the segment. The analysis of this paper can take effective control measures to reduce the impact of cracks in shield tunnels on the normal construction of shield tunnels.

Guoxia-silaotuo fault is a part of Longxian-Baoji fault zone. In previous studies, people only inferred the spatial distribution of the fault from the indirect evidences of geomorphology and geophysics. In this paper, through the detailed investigation of the fault, the outcrop of the fault plane is found; the trenching method is used to investigate the fault, and the activity scale of the fault is revealed. It is found that in the late Pleistocene, the activity intensity of the fault is relatively high.

Cold weather influents most parts of China in winter. Pavements are easy to freeze, and the frozen pavements can affect traffic safety and reduce traffic efficiency. For porous asphalt pavement, low temperature has more serious effect on it and it is easier to freeze. The paper takes porous asphalt pavement as the research object, simulates its freezing phenomenon in winter, and measures the ice thickness and freezing depth. The freezing process of porous asphalt pavement is deduced.

Traditional open-cut method for utility tunnel has many disadvantages such as long-term occupation and large area of land, great disturbance to urban traffic and environment, high labour intensity of workers and so on. In order to overcome the disadvantages above, a machine for prefabricated utility tunnel construction was designed which drawing on the working principle of shield machine and pipe jacking machine. The above-machine is applied in shulong road utility tunnel of Chengdu. The applicable results show that: (1) The above-machine achieve movable streamlined synchronous construction of earth excavation, components assembling and earth backfill. It improve the shortcoming of traditional open cut method and cancel the majority of foundation pit bracing structure. (2) The above-machine can make mechanized and assemblage construction of shallow excavation precast utility tunnel come true. It effectively control construction quality and reduce difficulty of construction management.

Garbage dam is an important structure of sanitary landfill, but there is no systematic stability calculation method at present. In this paper, the present situation of a garbage dam is investigated in detail, and it is found that the local settlement of the dam body is large, and there is the possibility of instability. Then, the soil samples were collected from the dam body and the indoor geotechnical tests were carried out. Based on the test data, the GEO-SLOPE software is used to carry out the numerical simulation analysis of the garbage dam. The results of the numerical analysis show that the safety factor of the garbage dam does not meet the requirements of the code, and there is a risk of instability. In view of the problems existing in the dam body, this paper puts forward the solutions for the reinforcement of the dam body, which effectively eliminates the problems of Seepage Damage and crack damage. The results show that the numerical analysis is correct and the reinforcement effect is effective.

The influence of limestone powder concrete on working performance and mechanical properties are researched under which it is changed substitution rate of rubber powder and mixing ratio of rubber powder with different fineness under equal substitution rate. Take C30 concrete as an example, two proportioning schemes are set respectively: The machine-made sand of limestone powder concrete is replaced by 20 mesh rubber powder equal volume; Under the specific constant volume rate of substitution, changing the mixing ratio of 20 and 40 mesh rubber powder to research working performance and mechanical properties of concrete. The results show that the substitution rate of 20 mesh rubber powder is less than 10%, increasing the slump of concrete. On the contrary, the slump of concrete decreases sharply and the flow performance weakens. The compressive strength of concrete decreases sharply when increasing substitution rate of 20 mesh rubber powder. When Increaseing the mix ratio of 20 and 40 mesh rubber powder under equal substitution rate, the slump of concrete increases and the compressive strength increases first and then decreases. Fixing the mixing ratio, the slump and compressive strength decrease with the increase of rubber powder substitution rate. When the mixing ratio of 20 and 40 mesh rubber powder is 2:1, the compressive strength of concrete is higher.

During the construction of No.3 connection gallery between huyong station and lvdaohu station of first phase project of Line 2 Foshan Rail Transit, water and sand kicks caused the large-scale settlement of tunnel segments. After comparison and selection of schemes, the rehabilitation scheme of abandoning the existing right line tunnel, shield machine starting from huyong station and heading to Lvdaohu Station by changing the line, is finally adopted. In order to prevent secondary disasters caused by the collapse of abandoned tunnels, the ground boreholes are used to fill the abandoned tunnels. During the construction, a series of key construction technologies have been formed, such as sectional backfill of abandoned tunnel, alternate backfill of underwater concrete and mortar, and prevention of pipe blockage. The results of core-drilling test and subsequent construction procedures show that the treatment scheme of abandoned tunnel is reliable and feasible, which can provide reference for similar projects.

In order to avoid the summer rainfall flood peak and improve the efficiency of rainwater utilization, many cities have put the construction of storage ponds on the agenda. However, the design of the foundation pit of the storage tank mostly adopts the design method of building foundation pit, that is, the foundation pit supporting structure will be dismantled after the main structure construction to a certain extent, so this has resulted in a greater waste of resources. In view of the above reasons, this paper proposes a economical foundation pit supporting structure of underground storage pond. This structure can be used as both retaining structure and pool body structure in the process of foundation pit excavation, which can reduce the waste of materials in the construction process and reduce the project cost. Through the calculation results of MIDAS-GTS software, it can be seen that the optimized structure has a good supporting effect in the process of foundation pit excavation, and can completely replace the temporary supporting structure in the original design scheme. The calculation results can provide reference for similar engineering construction.

In the process of shield tunneling, there is a risk of cracks and diseases caused by geological changes, construction process, design and other factors, and leads to the construction process and even engineering accidents. This paper analyzes the cracks on the top of the segment under the geological conditions of deep burial and high water pressure by analyzing the cracks of a traffic rail project in Shenzhen, and analyzes the reasons for the cracks under normal construction. Based on the conventional stress model of segment and the screening of surrounding geological and hydrological conditions, the model assumption of local stress of integral segment is made, and the modified idiom and beam method are adopted- The results show that under the geological condition of fractured water stratum, the sudden change of water pressure caused by rainstorm and the joint action of broken rock block and segment floating will lead to the reduction of segment top space and direct contact with rock stratum, which will exceed the normal pressure range of segment and lead to cracks in the top segment.

Coral reefs are widely distributed in Xisha Islands, which have special engineering properties. Coral reef geology from top to bottom is coral sand, coral gravel, coral reefs calcareous rock. Coral sand and coral gravel have the characteristics of mixed size particles, alternating accumulation of sand and gravel, great change of density and gradually coarsening from top to bottom. Coral reefs calcareous rocks are composed of loose bioclasts cemented, some of them are dense, and some of them are semi-cemented and weakly cemented. The geological age of the Xisha Islands within 50m was determined by carbon-14 radioisotope isotopic test. The bearing capacity and deformation characteristics of coral sand and coral gravel were analyzed by plate loading test, heavy dynamic penetration test, extra-heavy dynamic penetration test and standard penetration test. The physical and mechanical characteristics of coral reefs calcareous rock were studied by longitudinal wave velocity test, density test, porosity test and uniaxial compressive strength test.

Aluminum alloy has a lot of benefits including high strength, great ductility and low density. It is widely used in vehicle engineering, aviation, aerospace and so on. However, there is a higher requirement for aluminum alloy in these fields. For instance, higher strength, higher hardness, higher elongation and other performances are needed. Changing the content of certain elements, combination with graphene, plasma spraying and heat treatment might be four effective methods to improve the performance of the aluminum alloy. The experiments verify the effectiveness of each method. Still, there should be more studies on these methods to reveal the principle of each method.

Machine-made sand self-compacting concrete is a kind of self compacting concrete with machine-made sand as fine aggregate, which could fill formwork only by its own gravity, without concrete vibration. It is different from ordinary concrete in many aspects, such as fluidity, workability, and configuration method^[1]. As a new type of concrete material, machine-made sand self-compacting concrete mix ratio has been studied in depth by many scholars. However, there are relatively few researches on the practical application of machine-made sand self-compacting concrete, especially on construction methods. This paper discusses the characteristics and construction differences between machine-made sand self-compacting concrete and ordinary concrete, and proposes a special construction method for machine-made sand self-compacting concrete.

The deformation monitoring value of Hengli Island soft strata by vacuum preloading was analyzed. The results show that the vertical settlement and lateral displacement of strata mainly occur in the first 20 days. The negative pressure attenuation at different positions is quite different, and the average negative pressure attenuation rate with depth is about 3.2kPa/m. The difference of additional stress by the overlying water leads to the average settlement of the central area of the preloading area is greater than that of the marginal area. The settlement calculation results of Layered Summation Method are basically consistent with the measured values. According to the lateral displacement law of different projects, it is concluded that the lateral displacement has a progressive relationship with the vacuum preloading area half width, the prefabricated vertical drains (PVDs) length and the vertical settlement ratio of about 10 times, and the calculated value of lateral displacement agrees well with the measured value.

Elevation monitoring is an important step in the construction process of wide low tower cable-stayed bridge. In this process, it mainly controls the difference between the actual elevation and the design elevation in the cantilever construction process of beam section, and controls the formwork elevation value of each section of beam section construction, In the study of cantilever construction elevation monitoring method, this paper analyzes the engineering background and elevation detection process error analysis, elevation control value selection and elevation linear control analysis, and takes a wide low tower cable-stayed bridge as an example, combined with the actual test results to verify the method. It is concluded that the elevation correction error is controllable and the construction alignment is consistent with the design alignment. The vertical alignment error meets the specification requirements, which can provide reference for the elevation control of similar projects.

The stability of highway slopes after floods is related to the smooth operation of traffic, construction and other related projects along the road. Taking highway slopes in Guizhou Province as the research object, conducting InSAR monitoring and on-site surveys on them, and obtaining a large amount of slope characteristic data after flood, the main conclusions are as follows: InSAR technology can study the influence of highway slope stability after flood, therefore, it saves a lot of manpower and time cost, uses on-site survey method to count the relevant characteristics of the slope along the highway, and uses the index system method to evaluate the risk level of the slope. It is believed that the road slope is prone to poor stability after the flood, and the risk level is higher.

Taking sericite schist residual soil widely distributed along Dalin Railway as the research object, the resonance column test of sericite schist residual soil in unsaturated state was carried out, and the dynamic shear modulus G_d under different water content, dry density and consolidation confining pressure in small strain range (10⁻⁶ < γ_d < 10⁻⁴) was studied. The test results show that water content has a great influence on dynamic shear modulus, followed by dry density and consolidation confining pressure. G_d increases non-linearly with the increase of water cut, and there is a certain critical water cut that makes G_d reach the maximum, and then G_d gradually declines with the increase of water cut; D ∼ γ_d curves tend to overlap under high confining pressure and high water content. Under the same dynamic shear strain amplitude, G_d increases with the increase of dry density. Under different consolidation confining pressures, the increasing of G_d follow-up shear strain γd tends to decrease.

A new type of fabricated shotcrete sandwich wall system is proposed. The wall system consisted of steel mesh, foamed concrete blocks, reinforced concrete layers, and core column. The shotcrete has been adopts in structural layer. Steel mesh is placed in the concrete layer. Foam concrete blocks are filled between concrete layers with function of insulation. Core columns are arranged along the cross section of wall with spacing 600mm. Prefabricated rebar cage place in core column. The finite element software ABAQUS is used to calculate its compressive strength, and the calculation results are compared with the theoretical method of related code. The results show that the FE simulation results have a good agreement with the formulation recommended by code.

In this paper, a finite element model is established to study the influence of connection plate thickness on the bearing capacity of steel tube tower connections. Through the bearing capacity of connections under different connection plate thickness, the influence of connection plate thickness on the bearing capacity of steel pipe tower connections is analyzed. Finally, the relationship between the thickness of connection plates and the bearing capacity of steel tube tower connections is analyzed by regression analysis. The results show that with the increase of the thickness of gusset plate, the bearing capacity of steel tube tower connections increases linearly. The bearing capacity calculated by regression analysis is in good agreement with the finite element simulation results.

Based on the experiment and grey system theory, the influence on slump and compressive strength of rubber concrete are analyzed systematically under the rubber grain gradation mass, the content of rubber grain substitution and whether the rubber surface is pretreated. The influence rule of each factor on the slump and compressive strength is consistent. The influence order is as follows: The mass percentage of rubber particle grading is more than the amount of rubber particle replacing, which is more than whether the rubber surface is pretreated. The mass percentage of rubber particle grading and the amount of rubber particle replacing is more than 0.6 and whether the rubber surface is pretreated that is less than 0.6. In view of this situation, considering whether the assignment condition of rubber surface pretreated is reasonable, this problem needs further study. The results of this paper provide a theoretical reference for the main factors concerned in the mix design of rubber concrete.

This article mainly analyzes the technical practice of construction engineering geotechnical survey and construction treatment. This project describes the practical significance of geotechnical engineering survey for construction engineering. It analyzes the surveying techniques commonly used in current geotechnical surveys, such as geological surveys, surveying and mapping, and prospecting. Take a construction project as an example to illustrate the application of engineering geotechnical survey and processing technology. This study can provide reference and reference for construction engineering geotechnical survey work.

Based on the unsaturated seepage and strength theory, the influence of seepage on tunnel deformation and stability is studied, the mechanism of tunnel collapse under seepage is deeply analyzed, and the grouting reinforcement measures are put forward. The analysis results show that the strength attenuation of unsaturated soil caused by seepage is the main inducement of tunnel collapse. The development of tunnel collapse is controlled by conducting the backpressure of surcharge, improving the softening condition of soil, and grouting reinforcement of soil with weakened strength. Finally, the risk of collapse is effectively solved.

In order to adapt to the application and development of large-span steel structure, this paper takes a 19-story assembled hybrid staggered truss structure office building as the background. SAP2000 finite element analysis software is used to establish two different forms of assembled steel structure staggered truss system, namely the hybrid staggered truss structure and the vierendeel staggered truss structure. The seismic performance of the structure was analyzed by modal analysis and dynamic elastic-plastic time-history analysis. The main conclusions are as follows: According to the modal analysis of the structure, the directions of the first three modes of the hybrid staggered truss structure are different from those of the vierendeel staggered truss structure. However, the natural vibration period of the two structures gradually decreases with the increase of the vibration mode. The natural vibration period of the vierendeel staggered truss structure is obviously larger than that of the hybrid staggered truss structure, which indicates that the stiffness and quality of the hybrid staggered truss structure are both larger than that of the vierendeel staggered truss structure. Through the dynamic elastic-plastic time-history analysis of the structure, the seismic performance of the two staggered truss structures in the X direction is basically the same. The difference is mainly reflected in the seismic performance in the Y direction. The seismic performance of the hybrid staggered truss structure is obviously better than that of the vierendeel staggered truss structure.

Foamed concrete is a heat preservation and noise reduction material made of cement and aluminum powder as foaming agent. The experiment mainly studies the influence of different water-cement ratio, foaming agent dosage and cement dosage on the expansion rate of foamed concrete test block. The experimental results show that when the water-cement ratio increases from 0.4 to 0.6, the expansion rate decreases gradually. When the content of aluminum powder foaming agent increased from 0.05% to 0.40%, the expansion rate showed a trend of "increasing first and then decreasing". When other conditions are the same, the expansion rate of cement increases from 500kg/m³ to 800kg/m³, showing a trend of "decreasing first and then increasing".

The implicit and computationally time-consuming performance function limits the application of classical reliability analysis methods in complex structures. To facilitate the reliability calculation of civil engineering structures, a reliability analysis method based on genetic algorithm (GA) and Gaussian process regression (GPR) is proposed in this paper. In this method, GPR is adopted to build the surrogate model of performance function, and GA is used for infill-sampling to improve the model accuracy at the limit state surface. Replacing the actual function with this model in Monte Carlo simulation (MCS), the approximate failure probability can be obtained. Four examples are analysed to validate the efficiency and accuracy of the proposed method. The results show that it can deal with the problems of static reliability and seismic reliability, and can be well combined with structural analysis software, which is convenient for engineering designers to use.

The bracket set of traditional Chinese timber buildings in Jiangnan region plays a structural and decorative role. The research of it is of great significance for cognitive the characteristics of local traditional timber buildings. In order to further understanding the mechanical properties of typical bracket set in traditional timber buildings of Song and Yuan dynasties in Jiangnan region, the methods of field investigation and numerical simulation were used. The typical bracket set of traditional timber buildings of Song and Yuan dynasties were extracted. The construction practices, mechanical properties and importance of components were studied. The results provide a basis for conservation of bracket set effectively and scientifically.

Large-diameter shield tunneling in weak strata has the risks of segment floating, segment cracking and seepage, affecting the durability of the tunnel structure. In this paper, the statistical analysis of the cracks of a large-diameter shield tunnel segment was carried out, and the thickness of the force transmission liner was studied. The experiment showed that the average number of cracks per ring was the smallest when using a 3mm liner. Based on the structural characteristics of the segment, four types of stresses, namely simple support of segment boss, double-sided cantilever, single-point cantilever and two-point cantilever, and it is verified through on-site statistics, which has certain guiding significance for crack prevention.

In order to meet the requirements of people for the use of large space, the masonry structure building is underpinned, the load-bearing wall of the building is removed, and the underpinning beam is constructed to replace the original load-bearing wall to bear the upper load, the bottom masonry structure is transformed into a large space frame structure. Based on the analysis of two different underpinning methods, this paper selects the structural underpinning method according to their advantages and disadvantages, and takes an example as an example to summarize the construction of underpinning beam structure first. Then the main construction methods and matters needing attention of the underpinning technology for removing the load-bearing wall in the construction process, so as to provide a certain basis for the future construction of the structure. Through the displacement loading method, the bearing capacity of frame beam and underpinning beam is analyzed, and the data are processed, and the advantages and disadvantages of underpinning beam and frame beam under load are obtained.

Shield tail clearance is an important basis for the selection of segment assembly and shield attitude control. It is the most direct factor affecting shield tail brush wear. Poor shield tail clearance is prone to segment damage and shield tail seal failure. Using manual measurement of the shield tail gap, the measurement data has a certain hysteresis, and can not directly reflect the changing trend of the shield tail gap. Based on image recognition technology, a dual laser shield tail gap measurement device was developed to measure the changes in the shield tail gap during shield tunneling. The field test shows that: 1 The measurement device can monitor the shield tail gap in real time, and can simulate the ellipticity of the shield tail, monitor the deformation of the shield tail and the space state of the shield tail and the tube. 2 The acquisition device adopts a dual laser transmitter, meanwhile, the attitude of the shield machine cannot be controlled in real time, Can accurately establish the geometric relationship between the actual distance and the pixel distance, improve the test accuracy of the measuring device, and control the monitoring accuracy at 3.8 mm.

The polished stone value (PSV) of a coarse aggregate indicates its ability to resist the polishing action of tires. In the measurement tests of PSV of coarse aggregates, due to the complicated process, artificial factors or instrumental performances may cause measurement deviations. In order to explore the influences of instrumental factors, based on the features and working principle of a pendulum friction coefficient tester, the main influencing factors were firstly analyzed and then experimentally verified through measuring PSV of andesite and basalt. With the one-variable linear regression method, the testing data were fitted in order to determine the variations of the PSV of coarse aggregates with the hardness of rubber strip used in the slider block and the axial deformation distance of the slider block corresponding to the maximum positive static pressure on the tested surface. With the increase in the hardness of rubber strip, the measured PSV increased. With the increase in the axial deformation distance of slider block corresponding to the maximum positive static pressure on the tested surface, the measured PSV decreased. The quantitative analysis of the factors affecting PSV can improve its determination accuracy.

In view of the shortcomings of traditional methods in the quality inspection of large-scale topographic maps in Alpine area and high altitude areas, such as the difficulty of operation and the limited coverage of detection points, this paper puts forward the method of UAV tilt photogrammetry. This paper attempted to replace the traditional quality inspection method in the quality inspection of mathematical accuracy of large-scale topographic maps. By constructing the three-dimensional real scene model of the target area, this paper studied a new method for the quality inspection of large-scale topographic maps, which breaks through the fixed mode that the traditional quality inspection can only be checked by on-the-spot collection, further improve the accuracy and objectivity of the results quality inspection, intensive manpower and material resources, and improve the efficiency and quality of the quality inspection work. Comparing with the traditional check points collected in the field, the UAV tilt photogrammetry method can replace the traditional quality inspection method in the quality inspection of mathematical accuracy of large-scale topographic maps.

The fisheye image has severe distortions, which is not in line with human visual habits and brings inconvenience to its application. This paper classifies them into spherical structural distortion and optical distortion, and proposes a fisheye image correction method based on 3D control field. First, the spherical transformation radius and the optical center of the fisheye image are accurately solved, and the fisheye image is corrected by combining the spherical perspective projection; then, the distortion model of the fisheye camera is introduced into the DLT model to calibrate the optical distortion, and the results are used to recorrect the image. This method has been experimentally proven to be fast and effective.

The landslide susceptibility mapping and hazard warning are widely adopted tools by the government, stakeholders and the public for landslide disaster preparedness and emergency planning. This study presented a modelling tool based on geographic information system (GIS) and machine learning to aid the two-step modelling procedure. The machine learning methods including artificial neural networks, support vector machines, and logistic regression were integrated into the GIS environment for modelling landslide susceptibility to simplify and automate the routines of model training, verification and prediction. Then, the meta-element model was employed to take the landslide susceptibility, antecedent effective rainfall and 24-hour forecasted rainfall as inputs to determine the landslide hazard level. The architecture to deploy the established meta-element model for real-time landslide hazard warning was also proposed. A study case in Chunan, China was selected to demonstrate the applicability of the modelling tool to aid landslide susceptibility mapping and real-time hazard warning in response to a typhoon event. The developed modelling tool was desired to evolve into cloud computing architecture to facilitate easy-to-reuse and uplift its scalability.

Timely and accurate grasp of land salinization status and its matching relationship with land use is the basis for scientific improvement of saline land and rational land use. The current land use types of Shouguang City on the south coast of the Bohai Sea were obtained based on Landsat 8 OLI multispectral images using supervised classification. And the spatial distribution map of land salinization was obtained by IDW interpolation. By superimposed analysis of the current land use types and the spatial distribution of salinization, the information of salinization degree was obtained. The matching relationship between salinization and land use was analyzed from both quantitative and spatial aspects. The results show that OLI multispectral image and filed survey can improve the extraction accuracy of land types and salinization degree information. The distribution of salinized land in Shouguang City has prominent regional characteristics, with non-saline, mild, moderate, severe, and saline soil distributed in a pattern of "large concentration and small insertion" from south to north. The spatial consistency of land use and salinization in Shouguang is remarkable, forming spatial characteristics of "vegetable in the south, grain and cotton in the middle, and fishery and salt in the north". However, no matter from space or quantity, the land use and salinization in Shouguang City have the problem of "overall match, local mismatch". It is suggested to take differentiated measures to regulate land use according to the current situation of distribution characteristics of land salinization and utilization.

Precise leveling is an important part of engineering construction project. With the increasing requirements of engineering construction projects, the demand for smart leveling is also increasing, but in the actual survey operation, there are many shortcomings in precision leveling, which has a certain impact on engineering project construction and scientific research. Through the comparative analysis of one-way leveling and two-way round-trip leveling, it is found that there is still uncertainty in the replacement of two-way round-trip leveling by one-way leveling.

The delimitation of rivers and lakes is the basis for clarifying the management scope and protection scope of river courses and lakes, and implementing the property right system of natural resources and effective management of natural ecological resources. The development of UAV low altitude photogrammetry technology provides a strong support for river and lake demarcation in terms of cost, efficiency and quality. In this paper, the reliability of the data in the test area is verified by selecting the project test area, and the feasibility of the application of consumer UAVs in the river and lake demarcation project is obtained, which provides some technical reference for the application of consumer UAVs in engineering projects.

The accessibility of electric vehicle charging stations (EVCS) is one of the critical factors affecting energy vehicles' development. It is also the root cause restricting the replacement of fuel vehicles by new energy vehicles. All kinds of dynamic factors in the city, such as population and traffic, will directly affect the spatiotemporal accessibility of charging service facilities. Therefore, exploring the measurement method of EVCS spatiotemporal accessibility in dynamic time-dependent environments can reduce idleness, alleviate queuing pressure, and promote new energy vehicles. Taking Nanjing as an example, this paper conducts research based on multiply time slots, mobile phone records, and online route planners. It uses population data dynamic effect measurement methods, traffic congestion coefficients, and 3SFCA based spatiotemporal accessibility models to evaluate the time slot changes of EVCS accessibility. The results show that with the changes of the urban population, occupation, residence, work, and leisure, the accessibility of EVCS presents prominent "polarization" characteristics and dynamic effects. It is recommended to formulate new and adjust the deployment plan of EVCS according to the dynamic changes of the urban population, traffic environment, and accessibility in multiply time slots to reduce idleness and queuing and improve the utilization rate of EVCS.

The petrographic study of the piedmont potassic belt indicates that the rocks in the piedmont potassic belt of Hadamengou gold deposit are mainly composed of potassic feldspar, plagioclase and quartz, which are distributed in a scattered form, and the rock fragmentation structure is widely developed. The study of element geochemistry and other aspects shows that the rocks in the piedown potassified zone are mainly composed of potassium feldspar, plagioclase and quartz, followed by a small amount of sericite, epidote and kaolin. The main elements mainly contain high K₂O and low Na₂O, and the K₂O/Na₂O ratio is higher than 2, all of which belong to the hyperpotassium series rocks.

Unmanned Aerial Vehicle image analysis technology has become an effective means to classify crops. However, the UAV image classification mostly adopts shallow learning algorithm, with few computing units. These methods have low recognition accuracy and poor generalization ability. Deep learning has powerful function expression and excellent feature learning abilities. The learned features have more essential character for data and have achieved remarkable results in image classification. Therefore, the study proposes a crop classification method based on Unmanned Aerial Vehicle image with deep learning and spatial and spectral feature fusion. The method uses deep convolutional neural network to classify Unmanned Aerial Vehicle images. Simplified AlexNet network structure, which reduces the number of network layers, was used to accelerate the convergence speed of the model while ensuring the accuracy of crop classification in practical applications. Then, the vegetation index and height features of the Unmanned Aerial Vehicle image were extracted. Feature combination and comparative analyses were carried out to find the most effective feature combination and improve the accuracy of crop classification through spatial and spectral feature fusion. In addition, a Sample Expansion Strategy was used to optimize the classification model and further improve the classification result to achieve a perfect performance in the crop classification of drone images. The experimental results showed that the deep learning method can effectively identify crop types in Unmanned Aerial Vehicle images, and the overall classification accuracy is raised from 86.07% to 92.76% when combining spatial and spectral feature fusion with Sample Expansion Strategy.

The post-earthquake building damage investigation is an important part of the earthquake emergency rescue work. It is a prerequisite for the ability to determine the location of the buried people and rescue the victims in the shortest time. Therefore, the timeliness of the post-earthquake building survey is a significant factor. The 3D reconstruction model of buildings based on UAV tilt photography has the advantages of multi-angle and three-dimensional, but it is too time-consuming. Therefore, this paper proposes a UAV tilt photography route planning algorithm. This algorithm improves the efficiency of the three-dimensional reconstruction of the building and saves valuable time for emergency rescue work. The algorithm requires two drone flights. During the first flight, the drone flies horizontally to get the aircraft POS data. With the POS data, the corresponding feature points on the ground will be obtained. According to the clustering of the feature points, the building oblique photography path planning area will be generated. Finally a reasonable drone route planning will be produced. During the second flight, the flight route generated by the algorithm was used to take oblique photography of the building to produce a three-dimensional reconstruction model. The final building model will be obtained based on the combination of the models obtained from the two flights. After contrast experiments with traditional oblique photography, the algorithm in this paper is significantly superior to the traditional oblique photography method in terms of building 3D reconstruction efficiency.

Detection and identification of individual trees are becoming increasingly important for forest related applications. Current, researches mostly concentrate on the segmentation of canopy height models (CHMs), which only produce rough tree delineation and numbers. Considering that different trees have changeable economic value and growing speed, this approach proposed a robust workflow that detects not only the location and shape of single trees but also the basic tree type. First, the multiple source point clouds are combined and classified to build the CHMs, based on the geometric information. Then, the tree tops are extracted based on the mathematical morphology operations. The tree delineation are then grown based on the tree tops and the competition among adjacent tress is considered. Finally, a multi-view projection based classification network was developed to identify the tree type, which meanwhile indicate the connecting trees that are hardly separated in CHMs. Experiments results on various data source demonstrate that the proposed approach can produce significant improvements on the detection results than existing researches.

Aiming at the problem that demographic data cannot visually and clearly show the true distribution of population and cannot be combined with other environmental resource spatial data for analysis. This paper takes Chongqing as an example, selects nighttime light data etc. as variable factors affecting population distribution. Using the Xgboost model to build a regression model on the county level, and generates the population data of 100m in Chongqing in 2010. The accuracy of the population spatialization results and three public data sets were compared on the township scale. Finally, based on the importance of the variable factors of the Xgboost model, the influencing factors of the spatial distribution of Chongqing's population were explored. The results show that the root mean square error in this paper is significantly better than the other three population data sets, the absolute value error is significantly better than the GPW data set and the Chinese kilometer grid data set, and slightly better than the World Pop data set. Through the analysis of the importance of variable factors, it is found that the distance from construction land is the most important indicator, and the nighttime light data, residential area and POI data all play an important role in population distribution of Chongqing.

For evaluating the objective measured by the traditional measurement technology that is continuous and periodic single point observation method, it is one-sided and uncertainty. The 3D laser scanning technology called the real scene reproduction technology can provide the support for the 3D design of all kinds of tested objectives in the favorable data. It not only simplifies the construction project cost and improves the work efficiency, but also the results of its data evaluation are more reliable and comprehensive. In the past ten years, the terrestrial laser scanner as a physical representative of the three-dimensional laser scanning technology has been applied in some industries such as electric power, archaeology, factories, cities, Bridges, hotels, ships, criminal investigation to represent its immeasurable value. In this paper, these cases applied in the hotel, sculpture, landscape wall, karst cave are more representative to show a variety of terrestrial laser scanner applications.

Wilderness plays a key role in mankind's response to combat climate change and slow down the rapid loss of biodiversity. Wilderness protection is the basis and key to preserving biodiversity, and wilderness identification is the basis for wilderness protection. This paper identified the wilderness areas (WAs) and analyzed the spatial pattern of wilderness level using the data of terrain, vegetation types, land use types, roads, and night lights, and classified the wilderness level into levels 1 to 10, with level 1 indicating the highest level of wilderness and level 10 indicating the lowest. Only patches characterized by wilderness level 1 and a patch area of ≧1.0km2 are identified as wilderness areas in this study. The results showed that (1) the low wilderness (level 8-10), middle wilderness (level 4-7), and high wilderness levels (level 1-3) in the region were in mosaic distribution, which accounted for 52.98%, 14.81%, and 32.21% of the region land area, respectively. Low wilderness areas were mainly distributed in the eastern part of the region, the middle wilderness areas were in the west part of the region, and the high wilderness areas were mainly distributed in the southwest and southeast of the region. (2) The wildness areas accounted for 12.74% of the total land area of the region with presenting scattered distribution. Moreover, wildness area which exceeded 10% of the total wilderness area had 5 towns such as Lucheng, Ziwu, and Xincun, Xishelu, and Dadi, and the range of wilderness covered 7 vegetation types, of which 97.46% of the wilderness areas was in pure forests, with 55.2% of the wilderness distributed in the range of 1800-2200 m. (3) The wilderness areas in the region were almost unprotected. The number and area of wilderness patches that were covered by nature reserves only accounted for 13.24% and 13.19% of patch numbers and areas of the total wilderness. Consequently, this might make it difficult to achieve animal and plant migration and gene exchange between different wildness patches, and it was also difficult to implement effective protection measures.

When carrying out related test experiments of shipborne LIDAR, it is necessary to launch lasers to areas with different water depths and confirm the working conditions of LIDAR according to the received waveform conditions, to debug the LIDAR. There is no special introduction to the indoor platform for this kind of testing. This article proposes an indoor LIDAR experiment platform, which will focus on the basic settings of the laser, sink, and reflector in the experiment, the design ideas and rationality of the sink and reflector modules, the experimental steps, and how to effectively obtain the waveform. This platform has good applications in parameter correction, waveform acquisition, water depth measurement, and other aspects of LIDAR design.

With the depth of the Convolutional neural network(CNN) increases, CNN may lead to the problem of gradient disappearance. Simultaneously, single scale convolutional kernel may not reflect the complex spatial structural information in hyperspectral image(HSI). In addition, the CNN based approach regards the spectral band data on a single pixel of the HSI as a disordered high dimensional vector for processing, which does not meet the characteristics of the spectral band data. To tackle these aforementioned issues, a novel classification approach based on multi-scale densely connected convolutional network(Densenet) and bi-direction recurrent neural network(Bi-RNN) with attention framework is introduced in this study. Specifically, multi-scale Densenet is exploited to fully extract the multiple scales complex spatial structural information and utilize the strong complementary yet correlated spatial feature information between convolution layers, and Bi-RNN with attention is designed to obtain inner spectral correlations within a continuous spectrum. For comparison and verifying the effectiveness of our proposed method, we test the proposed method with nine other recently proposed methods on Salinas dataset, and the experimental results demonstrate that the proposed method can sufficiently exploit spectral and spatial information and outperforms other competitive methods.

Zhaoyuan City in Shandong Province, China was used as an example to explore the driving factors, constraints, and model parameterization using the FLUS-UGB model. Using observed data from 2018 to determine the model accuracy, the Kappa coefficient was found to be 0.8132, the overall accuracy was 0.8924, and the reliability was high. The forecast results show that, from 2018 to 2030, the urban land area growth rate of Zhaoyuan City was 11.40%, with the central and northwestern regions showing higher growth rates. The urban land area growth rate of Jinling Town was the highest at 42.53%, while Mengzhi and Wenquan Streets and Xinzhuang Town's urban land area growth rate exceeded 10%. Other towns' urban land area growth rate was less than 10%.

Since ancient times, earthquake disasters have always been one of the most harmful natural disasters, and it is necessary to reduce the damage caused by earthquakes effectively. The earthquake early warning is a new technology that has been gradually mature in recent years and can effectively reduce earthquake disasters. The ability to accurately and quickly predict the earthquake magnitude has become an important but difficult part of the earthquake early warning technology. Currently, many countries in the world have been engaged in the projects of establishing and improving the system of earthquake early warning, and completed two methods to predict the earthquake magnitude as a kind of earthquake early warning, namely, the method of characteristic frequency and the method of characteristic amplitude. In recent years, with the constant improvement of deep learning, the application of machine learning in determining the earthquake magnitude as an early warning has been showing great development prospects and application possibility.

Aeromagnetic compensation plays an important role in airborne magnetic survey to eliminate the magnetic interference from the aircraft. However, the aeromagnetic compensation methods at present still cannot suppress the interference to the extremely low noise level of a high-sensitivity scalar magnetometer due to the common assumption about the time-invariation and the linearity of the Tolles-Lawson model depicting the aircraft magnetic interference. In this paper, an adaptive method based on local linear regression is proposed to improve the precision of aeromagnetic compensation. Instead of only using the whole historical calibration data all at once to estimate the model coefficients in advance as the traditional approach does, the proposed method calculates the coefficients in real-time by local linear regression during an aeromagnetic survey, using not only the historical calibration data but also the online measuring data, and both of them are required to be similar in a limited time window. The measured data were used to test the proposed method and the experimental results demonstrated its efficiency.

The method of continuous GNSS carrier phase time transfer is studied in detail, and the cause of jump in carrier phase time transfer results is analyzed. The relationship between multi-day data jump and daily jump is deduced in theory, and the correctness of the deduced result is verified by the calculation result of actual measured data. Solution is given to abnormal data jump in carrier phase time transfer. A continuous time transfer method based on least square curve fitting is proposed to deal with abnormal jumps in observation data, this method uses the least square curve fitting algorithm to fit and replace the observed data at abnormal moments to achieve continuous time transfer. The method proposed in this paper are validated and analyzed with the actual measured data, and compared with the traditional GNSS carrier phase time transfer solution. The results show that the methos given in this paper can solve the problem of abnormal data jump to a certain extent, effectively improve the continuity, availability and reliability of time transfer results, and also improve the frequency stability of time transfer results.

With the development of economy, countries all over the world are experiencing urbanization at different speeds. As the largest developing country in the world, China is experiencing long-term and sustained rapid economic growth and large-scale urbanization. Chongqing, China is a municipality directly under the Central Government of the People's Republic of China. It is also a world-famous mountainous city and a comprehensive industrial city. As the main urban area of Chongqing, the population and land use scale are rapidly expanding, and the urban infrastructure construction is further promoted. This paper analyzes the land use change of Yubei District in recent 20 years, which is of great significance to guide the urban planning scientifically and rationally, control the scale of urban land use, and protect the limited arable land resources and ecological environment..

To verify the feasibility of applying Neutral Regression Equations to retrieve Landsat8 sea surface temperature (SST), and compares the retrieval accuracy and difference of the two thermal infrared bands, this paper establishes Neutral Regression Equations based on 32 MODIS SST training points, and uses buoy SST and MODIS SST to validate and compare the retrieval results. The results show that the Landsat8 SST retrieved by these Equations has high accuracy and good consistency with MODIS SST. Buoy SST verification shows that the root mean square error (rmse) of the two bands is less than 0.5°C, and the deviations range is less than 1°C; MODIS SST verification shows that the mean deviation(bias) of the 10^th and 11^th bands are -0.16°C and -0.22°C, respectively, and their deviations range is basically within ± 1°C; the retrieval accuracy of the 10^th band is higher than that of the 11^th band. Using Neutral Regression Equations to monitor the thermal discharge from Houshi Power Plant has achieved a wonderful effect, the temperature rise plume is jet-like, and affects a large range with a total area of 1.88km² and a maximum thermal pollution distance of 2.5km.

Unmanned aerial vehicle (UAV) platform, especially in image acquisition, has the advantages of low cost and convenience compared with other sensors platform. Due to the limitation of platform load and cost, small UAV integrated positioning and orientation system (POS) has low accuracy, which makes it difficult to accurately reconstruct the geometric position and attitude of the sensor at the imaging time. For this reason, this paper proposes an angle consistent constraint algorithm to improve the accuracy of exterior orientation parameters. In this paper, the small UAV images measured in the field are used for experiments, and the results show that the constraint algorithm can achieve high accuracy when the number of control points is small and the accuracy of initial values is low, which greatly expands the application space of images.

It mainly discusses the application of Excel in field leveling and traverse adjustment calculation in this thesis. Excel has powerful functions of formula editing and function, so we use it to process survey data. We realize the advantages of Excel software in the measurement data processing. It is convenient, flexible, simple, and clear. A good Excel calculation table can be used in future work. It only needs to adjust the original data without repeating the arrangement and design of calculation formulas. It can completely replace the programmable calculator and bring a lot of convenience to the work.

The terracotta warriors excavated from Qin Shihuang's mausoleum are precious materials of the Qin Dynasty. They have great historical, scientific and artistic research value and are considered to be the true portrayal of the Qin people. In anthropology, the measurement of head and face features is one of the important means to analyze the ethnic relationship. In this paper, the 3D laser scanner is used to collect the high-precision 3D point cloud data of the terracotta warriors, extract the head and face features of the terracotta warriors, and variance analyze (ANOVA) and cluster analysis with the collected head and face features of 29 modern ethnic groups. Variance analysis shows that there is no significant difference between the terracotta warriors and modern people in the shape of morphological facial length, bizygomatic breadth, nose height, the height of mucons lips, and mouth breadth. Cluster analysis based on head and face features shows that the terracotta warriors belong to the same group with 10 ethnic groups including Mongolian, and they have more similar head and face features.

Based on the field investigation of dam break cases, a numerical simulation method of concrete faced sand-gravel dam overtopping break is proposed. The method is mainly composed of three parts: (1) Aiming at the erosion and scour of vortex flow on dam body, appropriate model is used to simulate the flow movement; (2) The interaction between water flow and sand particles in dam break process is accurately simulated; (3) Based on moment balance method, the failure process of concrete face slab under dead weight and water load is determined. The results show that the proposed mathematical simulation method can accurately simulate the reverse erosion of the dam and the detailed evolution of the face slab break during the dam break process. The relative error between the measured data and the calculated peak breach flow, the development of the breach of the rockfill body, the duration of the dam break and the length of the face slabs are all less than 15%, which verifies the rationality of the numerical model.

Under the premise of ensuring safety, quality compliance, reasonable schedule, and lowest cost are the fundamental goals of construction project management. The realization of this goal, in the final analysis, will fall on the key point of cost management. With the advent of the "Internet + " era, the construction industry has developed rapidly, especially the application and promotion of BIM technology, which has gradually changed the traditional cost control mode. Based on BIM technology, taking construction project cost management as the research object, introducing the management method based on "BIM + earned value method", analyzing the application of BIM technology in construction project cost management, constructing a cost management practice model, proposing specific countermeasures, and guiding the project practice.

The grid structure is more and more widely used in the civil engineering industry, but due to the large number of rods and complex installation, it is extremely difficult to construct at high altitude. In order to overcome this problem, engineers proposed a hydraulic jacking method. The mechanical properties of steel structures are more complicated, especially in the construction process, the force situation and the design load is quite different. In order to explore the reliability of the hydraulic lifting process of the steel grid, this article takes the hydraulic lifting technology of the steel grid roof of a hangar as the engineering background. This project uses Sap2000 finite element analysis software to model, simulate the construction process of the jacking grid, analyze the mechanical characteristics and stability of the grid during the jacking process, and use it to guide the construction. The results show that: for large grid structures constructed at high altitudes and hydraulic jacking technology can effectively improve the construction efficiency and safety.

The State Council of our country has put forward the idea of gradually opening up the completed residential quarters and unit compound, which has a different impact on the traffic of the roads around the residential quarters and a reasonable analysis of the index system, and then uses the analytic hierarchy process to study the impact of the opening of the residential quarters on the traffic of the surrounding roads.

Population aging is a global problem in the 21st century, especially in China, where the elderly population is huge and has become a severe social reality. Therefore, how to make the elderly enjoy their old age and spend their old age happily in the community environment is a problem facing the current society. In this paper, CNKI is taken as the literature source, and relevant keywords such as community aging landscape and elderly community landscape from 2010 to 2020 are searched. The related research hotspots in recent ten years are analyzed by VOSviewer data visualization software, and the current research status is briefly described. It can be seen from the analysis that the research methods are gradually scientific and systematic, and the research hotspots are gradually changing from the formal landscape of the elderly community to more practical and targeted target landscapes such as health care and healing, microclimate and gardening therapy, and the trend of cross-disciplinary research is gradually obvious. On this basis, this paper attempts to analyze the future development trend of the aging community landscape by domestic scholars, with a view to providing help for further research.

It is one of the goals of outdoor space design in hot summer areas to construct a "constant-holistic shadow" space for outdoor people that can always be in the shadow during the required period of time in summer. However, the relevance and process of design elements related to the space of "constant-holistic shadow" are different from those of conventional design, as well as methods, stages and objectives of design intervention. Therefore, it should be controlled according to appropriate stage design objectives and contents. Based on the relationship between the design goal and the design process of "constant-holistic shadow" space, this paper analyzed the feasibility of the design process intervention under the construction goal of "constant-holistic shadow" space and clarified the corresponding design intervention process and strategies. It is expected to provide green design ideas and methods for promoting the utilization efficiency of summer shadow and optimizing the thermal comfort of outdoor public space in summer hot areas, as well as enrich the relevant theories and methods of outdoor public space design.

With the global warming in the future, the meteorological data based on the Typical Meteorological Year (TMY) can no longer accurately reflect the changes in building energy consumption under future meteorological conditions. This paper selects the typical meteorological year (TMY) in the Yangtze River Delta region as the base year data and the monthly scale forecast data provided by the IPCC, and uses the "Morphing" method to predict hourly weather data in 2050 and 2080. The use of energy simulation software Energy Plus of the Yangtze River Delta region in a passive multi-storey residential building energy simulation, analysis of building energy performance under future climate change, projected changes passive residential building energy demand over the next 60 years of trend.

Based on the test results of series quasi-static tests carried out by JSCE Committee, the rationality of the numerical model for quasi-static test of soil-underground structure system was verified. Then a quasi-static pushover test scheme was introduced, the verified numerical model was adopted to study the reasonable range of soil width in the quasi-static pushover test of soil-underground structure system. The results indicated that for this quasi-static pushover test scheme, when α (α is the ratio of the distance from boundary to the model structure to the model structure's width) is 0.5 to 1.2, error of the seismic capacity of the key structural components obtained by the test method is relatively small.

Prefabricated assembly technology has become an important direction for the development of subway underground stations. Comprehensively considering the three factors of stress, waterproof and construction environment, this paper proposes a set of prefabricated and cast-in-place assembly plans for subway stations. On the premise of ensuring that the overall stress form of subway station frame does not change significantly, the detailed prefabricated joint structure is designed, which effectively solves the waterproof problem of underground structure. The combination of permanent column and temporary column is realized, the investment of formwork support is reduced, and the assembly construction process of subway station is greatly simplified.

In the process of construction industry development, due to the slow development of information technology, low level of fine management, various working modes and other problems, it is difficult to form a benign closed loop among construction participants in the planning and decision-making stage, design stage, construction stage, production stage, operation and maintenance stage of the project. This paper proposes the concept of intensive management of intelligent construction based on BIM technology to realize the integrated development of the whole life cycle of buildings. Through studying the connotation, development status, research significance and function of intensive management of intelligent construction, the paper constructs an intensive management system of intelligent construction based on BIM technology, which realizes the independence and interoperability of each stage of the project, thus promoting the industrial upgrading and technology application of the construction industry and realizing sustainable development.

With the rapid development of construction industry and the large discharge of construction waste, there are many environmental problems. In order to formulate and implement the strategy of reducing management at the project level, it is necessary to estimate the amount of construction waste production accurately. Based on two methods, the building area method and the BIM method are used to estimate the amount of construction waste generated by a new residence, and a comparative model is established. According to the results, the method based on BIM can accurately estimate the amount of residential construction waste, improve the management level of residential construction waste and reduce environmental pollution.

The current research status of seismic lateral bearings and blocks of small and medium span beam bridges are briefly reviewed. The current research status of the block and bearing is analyzed and discussed, and the future research trend is discussed. The research results show that the research on the bearing is focused on the discussion of the mechanism and influence of the friction coefficient, friction force and slip performance of the plate rubber bearing; in terms of the stop, various new stop structure forms emerge in an endless stream; with the in-depth research of the two, Researchers began to pay attention to the mutual interaction of the support and the block when the actual earthquake occurred, and began to test the conceptual design, but how to fully consider the overall seismic performance of the bridge under the interaction of the two in the small and medium-span girder bridge The impact of this requires more in-depth research.

In the planning practice of Yuanbaozi Wetland Park in Zongzhai Town, Xi Ning City South New Area, planners insist on building five core functions with nature as the base and culture as the vein, so as to build a plateau city ecological wetland integrating ecological conservation, cultural experience, tourism distribution, popular science education and image promotion. They always put ecological protection in the first place, and each division combines landscape function with ecological protection, which provides a model for the planning practice of other urban wetland parks.

With the development of China's economy, the status of the pillar industry of the construction industry has been highlighted. However, compared with developed countries and regions, the construction industry in China generally has many problems such as large energy consumption, weak management, low level, low profit, and dense personnel. The prefabricated building has entered the public's vision. The prefabricated building has the advantages of energy saving and emission reduction, reducing environmental pollution and high work efficiency. Therefore, the prefabricated building has become an essential construction method for the development of the construction industry. Although the assembly type has many advantages, but the complicated information, complex technology, design refinement and other problems restrict the assembly type technology level in China. Therefore, it is necessary to combine BIM technology to carry out prefabricated component deepening design, daylighting and energy saving analysis, three-dimensional visualization analysis, construction scheme simulation, site layout process analysis, quality process monitoring, etc., to find complex problems in design and construction and conduct visualization research. This paper takes a complex project as an example to carry out the whole process of BIM application in prefabricated building design and construction, which makes the building realize the integrated innovative design of structural system, electromechanical system and prefabricated construction. The maximal adaptability to the space of the complex building is created, resulting in a high quality construction that adds significant value.

For the protection of historical buildings, in addition to the policy and legal provisions for the protection of historical buildings, it is also necessary to consider the traditional architectural form, craftsmanship, materials and other factors for specific historical buildings, and adopt appropriate restoration techniques. The text analyzes the common causes of damage to historical buildings in Macau, provides corresponding repair techniques to deal with the causes of damage, provides references and functions for the restoration of historical buildings, and avoids secondary damage caused by improper repair.

With the arrival of the era of stock optimization, urban existing industrial areas and industrial buildings through renovation and upgrading to improve the building performance and expand the building function, more and more become an important content of urban renewal. With rich industrial building heritages in Shanghai as an example, the study was based on the ground of the industrial heritage protection status and function of underground space utilization, exploring the development and utilization of underground space to realize city both with industrial zone industrial building heritages protection development, expansion of land space and function optimization, summarized based on the industrial building heritages protection of underground space utilization patterns and their characteristics. It can provide a reference for the existing urban environmental stock renewal and expansion.

Normal information spread estimation method (NISEM) is an effective method to infer the geotechnical parameter probability density function. However, it is found that the optimal bandwidth calculated by the existing method is not consistent with the actual situation in engineering application. In order to determine the matching bandwidth of NISEM, the histogram grouping number and group distance according to the sample quantity and range are first determined in this paper. Then the bandwidth h of NISEM is calculated, taking h as the benchmark, 0.1h as the step to change bandwidth. And combining with judgment coefficient, the optimal matching bandwidth of NISEM is finally obtained. The validity and rationality of the proposed method are verified by geotechnical test data of two groups of large samples and four groups of small samples in practical engineering. The results show that: under the condition of limited geotechnical samples, the best matching bandwidth is related to the number of histogram groups, which is relative. And the bandwidth of each group of test samples is different. The research work in this paper perfects the application of NISEM in inferring geotechnical parameter probability density function.

This project is a complex over-limit multi-storey structure. The structural over-limit items were analyzed, key parts were adopted to improve the seismic grade, the frame column was made of reinforced concrete column, and the thickness of the floor slab and the reinforcement were designed. The conversion truss was located on the 4th floor, with a span of 25.2m, and adopted H-shaped steel member steel truss. The performance-based design of the structure only meets the requirements of the supporting column conversion truss and related vertical members, and meets the non-yielding of large earthquakes.

In this paper, a case study is conducted of Wangmu walled-village, a traditional village in Dapeng New District, Shenzhen, China. It introduces the historical evolution, location overview and current situation of typical traditional Hakka's walled-village in the eastern part of Shenzhen. With Wangmu walled-village as an example, the settlement space and architectural value of existing walled-village are analyzed. Further, based on a value judgment, the feasibility of activation and application of Wangmu walled-village in the future is explored. An activation scheme is drawn up based on the current situation of the walled-village. Those will provide ideas and suggestions for the activation and promotion of similar traditional villages.

In this paper, the traditional revival architecture works of four prominent Chinese and Western architects in China are considered for the purpose of analyzing the external form of the roof curves in conjunction with the internal function of the roof truss. The differences between Western roof truss structure and Chinese traditional one in forming the characteristic roof curves of each cases are clearly brought out. The investigation reveals the adaptive and mutual influence of the Western structural systems and Chinese architectural elements on each other, and reflects on the significant contributions of Chinese and Western architects in the modernization and transformation process of traditional revival architecture.

The construction of the underwater tunnel of the Karnaphuli River in Bangladesh boasts the characteristics such as short time limit, small working shaft space and a large weight of the shield tunneling machine and etc.. Moreover, the translation and rotation of the shield tunneling machine are the key link of the entire construction, which also takes a longer time and is more difficult to achieve. The existing rotating technology of a shield tunneling machine and its applicable conditions were analyzed to conquer the difficulties like the tight time limit and the high mechanical level of disassembling and assembling of the shield tunneling machine in this project. The technology of integral translation and rotation of the large-diameter steel sleeve of the shield and the shield tunneling machine was proposed according to its characteristics and the present situation of confined working space. The technology mainly includes the design and application of the new steel ball base, the preparation of the working shaft space and its base, the leveling and translation of the shield tunneling machine, the translation of the shield machine, and its rotation at 180° in situ. The sliding friction between the sleeve base and the bottom plate of the working shaft is turned into rolling friction by the new steel ball base, which can effectively reduce the resistance of the translation and rotation of the steel sleeve. In a word, the working efficiency can be highly improved and the construction period can be shortened.

At present, the continuous development of the construction industry is inseparable from the support of BIM technology. In the construction industry, the construction of steel structures is particularly prominent. With the rapid development of steel structure engineering and the continuous advancement of technology, the technology of BIM has been produced. It is the integration of the two that led to the BIM technology. Only in this way can it play the key to ensuring quality in the construction of steel structures, so it can be said to be an indispensable technology. Therefore, the application of BIM technology in the current steel structure engineering construction can be very beneficial to improve work efficiency, quality assurance and project inventory budget. For this reason, this article analyzes and recommends the application of BIM technology in steel structures.

A maintenance hangar of in Guangzhou Baiyun International Airport was selected as an engineering case to show a novel technology of ground joint construction presented in this paper. The construction of the ground joint was described in detail and some conclusions were therefore summarized to show the effectiveness of the technology. The total area of the test section is 33000 square meters, which made a great difficulty in construction process. In order to avoid cracking in concrete, the ground concrete was casted by block and a new implement name "armor seam" was used to control boundary between different concrete blocks. After the implementation of new technology and implement, the flatness and wear resistance of ground, the compactness and integrality of concrete all had great improvement.

In 2005, Macau was merged into the World Cultural Heritage List with the Historic District of Macau. In addition to strengthening the protection and revitalization of the 22 buildings and 8 square fronts in the area, the Macau government has also unearthed a number of historical and cultural heritages. Historical buildings of cultural significance, such as General Ye Ting's Former Residence, Former Chong Sai Pharmacy, and the Patane Night Watch House. The long historical memory of Macau and even the Lingnan region. This article sorts out the protection process and common measures of Macau's heritage buildings. Through the study of Macau's heritage buildings, it discusses specific measures for the protection and activation of heritage buildings, which has a reference for the sustainable development of heritage buildings.

In the interior decoration industry, disputes between design and actual effects, waste of materials, and poor construction quality often occur. In order to improve customer satisfaction, reduce waste of construction resources, and realize smart decoration in the interior decoration industry, BIM + VR technology has begun to take the stage. BIM + VR interior decoration technology is the use of BIM technology to build a three-dimensional model to realize the three-dimensional visual display of the decoration design plan. Users can really feel the effect of interior decoration through VR technology, and modify the unsatisfactory parts of the design before construction, which can more accurately meet the needs of users. And finally achieve the smart decoration function.

Through in-depth research on landscape design, it is found that VR technology can indeed improve the visualization, accuracy and immediacy of landscape architects during the research process of landscape design. This technology will bring a revolutionary development in the process of landscape design, and through this technology, 3D vision related information can be connected between virtual and reality. This allows landscape architects to perceive the ecology and concept of design from the five senses, and virtual reality technology also provides a certain theoretical research foundation for future landscape design. To a certain extent, it is conducive to the optimization of the interactive experience of landscape architects. The solution ideas of derivative mixed reality (MR) and augmented reality (AR) are also proposed, as well as the prospect of future development.

Energy-efficiency residential building, based on the concept of green building, aims to solve the new field of residential problems. The purpose of the development of energy-efficiency residential buildings is to provide livable buildings for people with the lowest energy consumption. It reduces energy consumption throughout the life cycle of the building and contributes to sustainable development. However, this study finds that there are many obstacles in the process of promoting the use of energy-efficiency houses. There is not sufficient government support. Real estate companies avoid the promotion of energy-efficient buildings on a large scale by pursuing the maximization of profits. Buyers are blindly buying due to a lack of energy-saving awareness and related knowledge. To solve these problems, through literature research, this paper shows the progress status of the domestic energy-efficiency houses, excavated the existing obstacles, and attempt to offer specific measures and methods to break the obstacles from the three dimensions of government, enterprises and customers.

The Wu Gorge section of the Three Gorges Reservoir is prone to landslides and collapses of rock masses, which poses considerable threats to the transportation safety along the watercourse of Yangtze River. The oblique aerial photography technique can accurately present the profile and texture information of the observed objects, which can provide data for early detection of geological hazards. In this study, the technique of oblique aerial photography was analyzed in depth, and the obtained oblique aerial photographs were combined with the position and orientation system (POS) data and the ground control points to build a three-dimensional model, and a geological disaster evaluation model was built based on such factors as geological conditions, landform, and hydrological conditions for geological hazard evaluation. Meanwhile, indoor interpretation and fieldwork surveys were performed to summarize the patterns of development and distribution of geological disasters, identify the major contributors to geological disasters in the study area, and master the characteristics of liability of the study area to geological disasters and hidden hazards.

During the acquisition of point cloud data by LIDAR, due to system and environment reasons, there will be a large number of discrete points and noise points in the obtained point cloud data, which will affect the extraction of target ground object information. In view of the noise introduced by the system itself and the environment where the target object is when the LIDAR is scanning, a de-noising method combining statistical filtering and bilateral filtering is proposed in this paper.

The vertical migration of hydrocarbons from oil and gas reservoirs to the surface and/or subsurface (i.e., microseepage) can induce mineral alteration that results in concentration of ferrous iron, clay, and carbonate minerals at the Earth's surface. These altered zones may be detected in remote sensing imagery based on their specific reflectance spectral characteristics; zones where three types of mineral alteration occur simultaneously reflect possible hydrocarbon microseepage locations with the potential for underlying oil and gas reservoirs. In this study, a fuzzy set based approach was used to integrate the results of principal component analysis (PCA) and band ratios (BRs). First, each selected indicative principal component (PC) and BR was treated as a fuzzy set, and a corresponding fuzzy membership function defined. The membership degree of each pixel, which indicates the possibility of the presence of specific altered minerals, was then calculated. Subsequently, the Gamma operator was used to fuse all fuzzy sets to create a new fuzzy set, which was then defuzzied and used to indicate the possible locations of hydrocarbon microseepages. The Sentinel-2 MSI data were used to illustrate the approach and the zones of hydrocarbon microseepage mapped.

This article stars from the construction land remote sensing detection at home and abroad research situation analysis, summarizes various analysis methods, using spatial information technology in the process of urban construction land scale spatial distribution of different land use types and the spatial and temporal evolution of urban ecological environment quality evaluation, simulation, scientific development and management to provide decision support for the city, at the same time can also be used for land use planning, it provides reference for ecological and environmental governance. This can improve and enhance the level of urban planning and management, guide and control the future direction of urban development reasonably, so as to promote the coordinated development of cities.

Carrying out the evaluation of the ecological environment of the mining area is the basis for the protection and prevention of the environment of the mining area. This paper takes Fushun West Open-pit Mine as the research area, uses the remote sensing image data of Gaofen-1 (GF-1) satellite, and uses remote sensing and GIS technology, firstly obtains high-resolution multi-spectral remote sensing images, and then extracts environmental information of the mining area from the images, such as vegetation coverage, water bodies, soil index, and then normalizes the ecological impact factors, and at last uses the comprehensive index method to construct a comprehensive evaluation model of the mining area's ecological environment to analyze and evaluate the mining area's ecological environment. The mining area ecological environment assessment method based on the Gaofen-1 satellite data is simple and easy to implement, and the evaluation results can provide a reference for understanding the mining area's ecological environment and make reasonable protection measures.

Purpose: Using Landsat OLI remote sensing images in the two phases of 2015 and 2020. Taking Nanjing as the research area. Based on RS and GIS technology, adopting maximum likelihood method for supervised classification, extracting and producing a land use classification map for the two phases of Nanjing from 2015 to 2020. And further, using the land use change transfer matrix to analyze and summarize the characteristics and laws of the dynamic changes of land use in Nanjing. Result: From 2015 to 2020 in Nanjing, the overall land use change showed "two reductions and four increases". The area of arable land and bare land decreased by 729.46 km², 332.31 km²; the area of u rban construction land, woodland, grassland, and water area increased by 448.39 km², 231.67 km², 216.87 km² and 164.84 km². And each land use type has a different amount of area conversion. Conclusion: The analysis of land use change based on Landsat remote sensing image research area can effectively predict the change trend of regional land use. It can provide a basis for the research on the driving forces of land use change in the region, and it can also provide decision-making support for the formulation of land-related policies in the region.

Monitoring and analysis of irrigated area is of great significance to evaluate irrigation benefit, agricultural drought situation and regional water resources utilization. This article selects MODIS surface temperature products from 2016 to 2020. Using the method of daily difference in surface temperature, eliminating the influence of precipitation, realizing remote sensing monitoring of irrigation intensity and spatial distribution of irrigation area. The results showed that the average number of irrigation times in five years was in the range of 6-8. Due to factors such as rainfall during the irrigation period, the overall irrigation frequency from 2016 to 2018 is less than the overall irrigation frequency in 2019 and 2020. On June 11, 2018, remote sensing images detected irrigation areas of Buzi Town, Longhe Town, Yangbei Town and Chenji Town, which were consistent with the data of irrigation areas.

As an important component of soil, soil moisture plays an important role in material and energy transmission between hydrosphere, biosphere and atmosphere. It is of great significance to accurately understand the spatial and temporal distribution of soil moisture in large areas. At present, the spaceborne passive microwave remote sensing could achieve the accurate surface soil moisture of large areas, but at the low spatial resolution (10-50km). Therefore, its application was restricted. In this paper, a downscaling algorithm of passive microwave soil moisture products based on C-band backscattering coefficient is developed, and the algorithm is verified by L-band PALS Radiometer data and C-band AIRSAR data, the correlation coefficient R between the soil moisture content and the measured value is 0.71, and the root mean square error is 0.053cm³ · cm⁻³. According to the verification results of measured data, the downscaling algorithm of soil moisture retrieval products based on C-band backscattering coefficient is reliable.

Satellite thermal infrared observation has advantages over other earthquake observation techniques. With MODIS remote-sensing images from the TERRA satellite, the thermal infrared brightness temperature difference variation rate was used to analyze the observation data prior to three Magnitude-7-and-above earthquakes along the fracture zone of Longmen Mountain, and the result showed that there were thermal infrared brightness temperature anomalies one to two months before these three Magnitude-7-and-above earthquakes, and the earthquakes took place along the boundaries of the area where the anomalies occurred. The observation data show that there have been five times of substantial anomalies in the study area, among which four times were correlated to earthquakes.

Field patrol is the main method of wildlife protection, which plays a very important role in the protection and management of natural resources and biodiversity in nature reserves. However, it is difficult to completely evaluate the patrol accuracy, because it is impossible to preset the animal site in advance. Based on patrol data collected from the First Ecological Guard Competition, the accuracy of patrol route, animal site and geographical factor of animal site and GIS method are evaluated and analyzed. The results show that: (1) the patrol route has the highest accuracy, and the average accuracy is 87.91%, which indicates that ranger could basically patrol according to the preset patrol route; (2) the accuracy of animal site is not as good as that of patrol route, and the average accuracy is 51.10%, mainly because recorded animals are not right, standardized and complete; (3) the altitude accuracy is high, the slope accuracy is very low. It is recommended that slope data would no longer be recorded in the future and be directly obtained by GIS method. The results are helpful to improve the patrol accuracy evaluation system.

Baiyangdian Lake is the largest wetland ecosystem in North China, which has a special strategic position, so it is of great significance to study its temporal and spatial changes. Based on the 112 Landsat satellite remote sensing data from 1984 to 2020, this paper extracted the thematic information of Baiyangdian Lake open water body, carried out the study on the temporal and spatial evolution of the Baiyangdian Wetland ecosystem, and analyzed its area change trend as "increase-decrease-increase-decrease again-increase again ". Among them, the Landsat7 ETM SLC-off satellite digital product with band noise during 2003-2012 was repaired, so that it can better reflect the mutation characteristics and overall laws of Baiyangdian Lake water body in the past 30 years. On this basis, the Baiyangdian Lake water quality parameters were inverted, and the conclusions drawn have certain reference significance for maintaining the ecological environment of Baiyangdian Lake.

Terrain data of road is the most commonly used basic data by the traffic department. The high-precision three-dimensional road data can restore the terrain features under the real scene, which has a wider application range. In order to obtain high-precision three-dimensional point cloud road data, taking the vehicle-borne laser scanning data as the research object, a method of ground filtering for ribbon road is proposed. First, the driving trajectory information of the road data collected by the vehicle is read. Then, according to the road characteristics, characteristics of the vehicle driving trajectory is used to control processing direction, and a grid index of the point cloud data is created. Second, feature descriptors based on the spatial distribution characteristics of road point cloud data are established, and rough road point cloud data is obtained. Finally, the profile data of the vehicle-borne laser point cloud in the vertical trajectory driving direction is extracted, and the accurate ribbon road and the micro-terrain data on both sides are obtained by the horizontal constraint line detection algorithm. The experiment and analysis are carried out by using two different ribbon road data. Experimental results show that the method can be applied to different road scenes.

The distribution of islands and reefs is wide, and the field survey cost is high and difficult. After the identification of islands and reefs, how to carry out effective monitoring is also a problem. By comparing three remote sensing monitoring methods, this paper analyzes the advantages of satellite remote sensing image to obtain islands and reefs area monitoring methods, and puts forward three methods based on satellite remote sensing to monitor islands and reefs area, so as to provide reference for islands and reefs area monitoring.

The method of continuous GNSS carrier phase time transfer is studied in detail, and the cause of jump in carrier phase time transfer results is analyzed. The relationship between multi-day data jump and daily jump is deduced in theory, and the correctness of the deduced result is verified by the calculation result of actual measured data. Solution is given to daily jump in carrier phase time transfer. Since the time transfer reference signal is a continuously running high-precision atomic clock signal, a continuous PPP time transfer method based on clock difference parameter transfer is proposed. The method proposed in this paper is validated and analyzed with the actual measured data, and compared with the traditional GNSS carrier phase time transfer solution. The results show that the method given in this paper can solve the problem of daily jump jump to a certain extent, effectively improve the continuity, availability and reliability of time transfer results, and also improve the frequency stability of time transfer results.

The RANSAC (random sampling consensus) algorithm is an estimation method that can obtain the optimal model in samples containing a lot of abnormal data. This algorithm uses a small number of points in the data to estimate the model, and then uses the remaining points to check the model. It is now widely used in computer vision image stitching. This algorithm has disadvantages such as slow operation speed and poor sample adaptability. In order to improve the efficiency of image registration, many researchers have made improvements on the basis of the RANSAC principle. This article introduces the principles and shortcomings of RANSAC, and introduces four ways to improve it in view of its shortcomings. The advantages and problems of the improved algorithm are analyzed to provide a basis for the field of image registration.

Hunshandake Sand has sparse vegetation and serious desertification, which is one of the main reasons for the dust weather in the Beijing-Tianjin-Hebei region. Dynamic monitoring of vegetation coverage in this area is of great significance for predicting sand and dust weather in the Beijing-Tianjin-Hebei region. Remote sensing technology has the advantages of large area, multiple time phases, and high accuracy. This study is based on the CCD data of the HJ-1A, using NDVI parameters as the main input parameters, and using an improved pixel binary model to invert the vegetation coverage of the study area. On this basis, the land use type data is used to extract another vegetation coverage of the study area during the period. The vegetation coverage in different periods of the study area is calculated by band to achieve the purpose of dynamic monitoring. The results show that desertification is common in the northwest of the study area, and the vegetation coverage is becoming lower and lower, while the vegetation coverage in the northeast and south is increasing, and the overall vegetation coverage in the study area is increasing. The experimental results are more consistent with the actual situation, which confirms that the improved pixel binary model has higher accuracy and a certain degree of universality, and the overall desertification control effect of the Hunshandake Sand is better.

The advance of the resolution of optical observation satellite requires more accurate image acquisition location and geometrical model, therefore, light deflection effect must be taken into account in the geometrical model. The deflection of light is a phenomenon of a deviation between the apparent position and the true position of the observed object, due to the relative velocity of the observer (the remote sensing satellite). This article firstly models the light deflection effect of the earth-observation process of satellite, using this model, the deviation of the "apparent" location and the "real" location of the ground target is calculated. Then the influence of the satellite observation pointing angle to light deflection effect is analyzed. In the end, the correction method of the light deflection effect is advised, and through emulation, we can see that the image acquisition location error can be greatly improved after the correction.

The frequent occurrence of red tides in China's coastal areas has caused huge losses to society and economy, and seriously threatened the coastal marine environment and ecological security. Based on the data of 30 years from 1990 to 2019, this paper analyzes spatial-temporal distribution characteristics of red tide in China's coastal areas. Our results show that 1557 red tides occurred in China's coastal areas from 1990 to 2019. (1) There were 961 red tides from 2001 to 2012, which was the high red tide period in offshore China, accounting for 62.00% of the total number of red tides. The number of red tides in the Bohai Sea, Yellow Sea, East China Sea and South China Sea were 117, 103, 588 and 153, respectively. Seasonally, 536 red tides occurred from April to September, accounting for 87.00% of the total number of red tides. (2) In space, according to the kernel density estimation, red tides are mainly concentrated in Bohai Bay, Yangtze River Delta, Pearl River Delta and other regions with relatively dense population and relatively developed economy, especially in Zhejiang Province and the estuary of the Yangtze River. The research in this paper is of great significance to the monitoring and prevention of red tides and water environment management.

The detection method based on UAV has attracted more and more scholars' attention. In this paper, the basic principle of gradient tensor is discussed firstly, and then the composition of gradient tensor system and the structure are described. After the length of baseline is determined by simulation, a signal collector based on ARM CortexM3 is designed. Through the collector, 12 channels of signals can be collected synchronously, and RTK time and position information are integrated into each frame. The information after framing is transmitted to the ground station for further processing.

The vision SLAM technology is the key technology of robot navigation and unmanned driving. In order to further study the accuracy of multi-view SLAM positioning and mapping applications, this paper combines omnidirectional imaging and SLAM technology, improves the existing technical model in the field of omnidirectional imaging, studies the pose map optimization and SLAM overall adjustment technology based on object constraints and global consistency, and carries out omnidirectional SLAM point cloud reconstruction and 3D mapping. Through the time synchronization experiment of Ladybug 5 Plus and Femtomes Mini2-D-INS, the two positioning results of the system and the GNSS measurement results are compared and analysed.

Reservoir prediction in the middle and late stages of development is not only to predict the sandstone, but also to define the specific location of Petroleum-bearing sandstone. The post-stack seismic data is superimposed on a multi-channel seismic data level, although the signal-to-noise ratio is improved to a certain extent, the average amplitude value is obtained in the superposition process, so that only the effective prediction of the sand body can be realized. However, the pre-stack seismic data can obtain the information of shear wave by the longitudinal wave. The characteristics of the shear wave that cannot propagate in the fluid can effectively predict the reservoir and fluid distribution. In order to further quantify the remaining oil potential in fault area, prestack seismic inversion technology and petrophysical analysis are used to determine the favorable oil-bearing area. On this basis, prestack geostatistical inversion is completed to further clarify sand body with high oil saturation. Combined with numerical simulation, it effectively predicts the residual oil distribution at the edge of fault and the precision of the remaining oil quantitative characterization results is high. The recognition rate of thick layer saturation is more than 90%, and the recognition rate of thin interlayer saturation is more than 70%, which can meet the demand of fine reservoir prediction.

In the context of increasing lake expansion on the Tibetan Plateau, which is sensitive to climate change, it is of great significance to strengthen the research on the characteristics of lake change and its response to climate change. This paper was designed to investigate the spatiotemporal variations of Aksai Chin Lake (ACL), a typical large lake on the Tibetan Plateau, by using Landsat MSS/TM/ETM+/OLI images during 1972-2018, and to quantitatively discuss the effects of climate on lake changes based on meteorological data from Shiquanhe station. During 1961-2018, annual mean air temperature and precipitation in this region increased at rates of 0.44 °C/decade and 1.35 mm/decade, respectively, with a mutation point of 1999 for temperature, while evaporation decreased at the rate of -54.3 mm/decade, with two mutation points in 1972 and 2014, respectively. The area of ACL had increased at an average rate of 2.51 km² per year, with a fluctuation of "slight expansion – shrinkage – rapid expansion – slight expansion – rapid expansion" during 1972-2018. Controlled by the topography, the ACL expanded to the southeast by 3851.6 m in total. In terms of the lake area response to climate change, air temperature and evaporation were the main factors affecting ACL area directly, while precipitation mainly regulated ACL by the indirect effect through air temperature and evaporation. Generally, rising air temperature, increasing precipitation and decreasing evaporation all contribute to promote the expansion of ACL.

When LIDAR measures the water depth, in most cases the echo signal is more complex, with more backscattering, and it is difficult to observe different parts of the waveform separately, especially the underwater echo signal. Therefore, this paper uses an STM32 controller to design a signal generator to send out pulse signals, which act on the detection device PMT in the LIDAR detection system to control the start and stop of the PMT receiving channel. By adjusting the frequency, duty cycle, and other parameters of this signal generator, the arbitrary part of the waveform can be collected, and the waveform is not disturbed. Using the STM32 instead of a traditional signal generator can reduce system power consumption and load capacity.

Aiming at the problem that the generalization ability of deep convolution neural network model is limited, this paper extracted the semantic information of buildings in different regions by combining the transfer learning method. Taking the Massachusetts aerial image building data set as an example, the layer depth structure of Segnet network model is improved, and a new model is trained by migrating the parameters of the improved model and combining with a small number of Guilin building image data samples. The extraction results were analyzed and compared. The results show that, by transferring the parameters of the trained model, the Kappa coefficient and F1 score of buildings in Guilin area reached about 0.8.

As the direct result of climate change, Spatio-temporal variation of vegetation cover is an important index in regional ecological change. Based on Google Earth Engine, MODIS-NDVI and precipitation of TRMM from 2000 to 2019 were extracted. Trend analysis method and PCCs were applied to explore the different scales temporal and spatial change of NDVI and the relationship between NDVI and precipitation in the upper of Heihe River Basin. It was found that the annual change of vegetation increased slowly in the study area, and correlation of vegetation NDVI with precipitation are insignificant. On month scale, the vegetation change was cyclical, there was a noticeable increase from June to September, but from November to next February, the vegetation coverage was the lowest, the change of precipitation had the similar variation pattern, and there was a strong positive correlation between precipitation and NDVI. In terms of spatial change, the NDVI rose generally from northwest to southeast, vegetation coverage in northwest was improved.

Based on the literature data of multi-source nighttime light research in the core database of Web of science from 2010 to 2020, combined bibliometric analysis and audit analysis, analysed by Cite Space software, the research results of multi-source nighttime light data are separately audited by integrated analysis, unit analysis, node correlation analysis and word frequency node classification. The main conclusions are: (1) After the initial and stable development of multi-source nighttime light data, it is in the rapid development period; (2) China and the United States are the main research countries (3) "City" is a research hotspot, and "China" is the main research object; (4) The research fields mainly focus on remote sensing, environmental science, imaging science and photographic technology, geography physical, and others.

China is the world's largest rice producer and consumer. Accurate identification of rice planting and irrigation area is of great significance to China's food security. Based on GF-1 multispectral data, spectral matching and OTSU algorithm were used to monitor the rice irrigation area in Chuanhang Irrigation Area from 2016 to 2020. The accuracy was verified by confusion matrix. The overall accuracy was 98.1691%, 91.8706%, 95.2451%, 93.0604%, 91.9697%, respectively. The Kappa coefficients were 0.9541, 0.7898, 0.8777, 0.8330 and 0.7824, respectively, which proved that this method was suitable for rice irrigation area extraction based on high spatial resolution remote sensing data, and could provide technical support for rice irrigation area monitoring in irrigated areas.

Qinhuangdao Port, as the main hub port for coal transportation from north to south, has become an important coal, oil and other energy export port in China. The port facilities are in continuous operation all the year round, especially in the peak period of coal transportation in the south. The maintenance and monitoring of the equipment are faced with such problems as heavy work tasks, poor working environment, many construction disturbances, and the influence of monitoring on port production. This paper mainly introduces the application of ground 3D laser scanner in building deformation measurement based on the deformation measurement project of positioning car cable track in the unloading department of coal terminal of Qinhuangdao Port. Through actual results illustrate using the ground three-dimensional laser scanner for high-risk, complex structure deformation monitoring operation is of field operation is simple, short construction period, small impact on the continuity of production equipment, complete data and reliable advantages of accuracy, which is the ground three-dimensional laser scanner in Qinhuangdao port for the first time application, for the future of 3 d laser scanning technology in the port risk measuring project and digital 3 d modeling and so on has certain reference value.

Based on 1871-2010 monthly sea surface salinity (SSS) and flow field data, and the global seabed topography data, the inter-monthly regional variation of SSS in different regions and their influencing factors are discussed after climate zoning in the East China Sea (ECS) and the adjacent Northwest Pacific Ocean (ANPO). Rresults show that: (1) the study area can be divided into the area of the ECS, the Kuroshio area of the East China Sea (KECS) and the ANPO I area, II area and III area. (2) In the continental shelf area of the ECS, the inter-monthly regional variation of SSS is significant, the inter-monthly variation range of feature points is large and the difference of SSS value at each point is great. (3) In the KECS, the inter-monthly regional variation of SSS is small. The SSS at feature points is high and the inter-monthly variation is small. From the inlet to the outlett of the KECS, the SSS value gradually increases. (4) In the ANPO, the inter-monthly regional variation of SSS is the smallest, the SSS at feature points is high, and their inter-monthly variation is small. The SSS increases with increasing longitude at the same latitude, and decreases with increasing latitude at the same longitude.

Traffic prediction is the key to intelligent traffic guidance, management and control. Aiming at the spatiotemporal characteristics of urban traffic and the complexity of nonlinear variation of traffic parameters, a long short-term memory network (LSTM) urban traffic condition prediction model (SA-LSTM) based on self-attention mechanism is proposed. SA-LSTM uses the self-attention mechanism to assign different weights to traffic state information in different space and time, reflecting the spatio-temporal correlation of traffic data prediction. It can also avoid the vanishing gradient problem faced by traditional RNN and improve the defect that LSTM cannot accurately express the different importance and spacio-temporal characteristic of traffic information. Based on SA-LSTM, experiments were conducted on the Shenzhen road network data and floating car data. LSTM and SA-LSTM were selected for Comparative verification experiments, and the results confirmed that SA-LSTM is superior to LSTM in multiple evaluation indicators. Moreover, the road spatio-temporal correlations obtained by traffic data analysis and obtained by model learning are highly consistent, which proves that SA-LSTM can precisely learn and express the spatio-temporal characteristics and changing trend of the traffic.

Based on the driving force test data of shape memory alloy (SMA), the constitutive model of SMA driving force is proposed, and the secondary development is carried out on the platform of OpenSees software. SMA material was added to OpenSees, and the results show that the calculation results in this paper are consistent with the experimental data. It provides a realization path for driving force finite element analysis using OpenSees platform.

To study seismic response of tank, 10 × 10⁴m³ vertical floating-roof tank model is established. The probability relationship between the intensity measure and engineering demand parameters is established based on extensive nonlinear dynamic time-history analysis. Four failure modes of tank were determined, and seismic fragility curve of under each failure mode was obtained. The results show that under frequent earthquake, the exceeding probability of circumferential tensile damage, and instability of tank wall in intact state were 40% and uplift of the bottom sheet was 75%. Under design-based earthquake and rare earthquake, circumferential tensile damage was in intact state, and the exceeding probability of instability were 66.9% in medium damage and 52.9% in severe damage. The exceeding probability of bottom uplift in severe damage is 90%. The method takes the randomness of ground motion into account, which can provide an effective idea for the evaluation of the seismic safety of tank structure.

Surface deformation and face failure may occur during shield tunneling in the shallow buried dry sandy stratum. The model shield machine is used to carry out the shield tunneling model test in dry sandy stratum. The surface deformation laws and the active failure process of the excavation face are analyzed by monitoring the surface deformation during advancing and face failure stages. It is concluded that the surface deformation curve is "M" shaped and asymmetrical about the tunnel axis. The surface settlement during face failure goes through two stages, and the surface collapse pit is approximately elliptical, whose center is located on the left side of the tunnel axis when the cutter head rotates clockwise.

Based on the comprehensive analysis of the existing major ship collision probability models, this paper combined the advantages of the AASHTO model and the KUNZI model and improved AASHTO model by using the ship simulator to obtain the ship's track probability distribution curve to replace the original geometric probability distribution curve. It also introduced ship stopping probability function to make up for the shortcomings of the AASHTO model in which the influence of human factors is not considered. Finally, this paper predicts the collision probability of the Longjiang Bridge in 2025 with the improved model.

The Fourier amplitude spectrum of acceleration will drop rapidly in the high frequency range. Anderson and Hough quantitatively studied the attenuation law of the acceleration Fourier spectrum above the corner frequency, and proposed the high-frequency attenuation parameter Kappa ( ) to describe this phenomenon. It has important applications in the field of engineering earthquakes, and is widely used by seismologists and engineers in the work of ground motion simulation and attenuation relations. Based on the Anderson method, this paper proposed a method of first smoothing the Fourier acceleration spectrum with a 0.4 Hz Parzen window and then fitting the solution value. The Fukushima earthquake data from Japan's KiK-net seismic network on February 13, 2021 was used to verify the reliability of the method. The results showed that when the width of the Parzen window was set to 0.4 Hz, the calculation accuracy of the value was effectively improved.

As a new trend of cultural heritage protection, digital technology has brought opportunities and challenges to the detection, protection and development of traditional villages. First, this article introduces the specific application of digital technology in the three stages of data collection, information processing and display and dissemination, and constructs the corresponding integrated application diagram, then summarizes the implementation obstacles in the protection process. Finally, a prospect is made for the development of digital protection of traditional villages. The results show that digital technology can provide a strong data foundation and flexible processing methods for the storage, restoration, display and dissemination of traditional village protection, and promote the transformation of single technology to multiple integrated applications.

Green building has an important impact on building design, so it should be emphasized. The application of green building design concept to housing design can better improve the design effect. But the use of green building design concept need to follow certain principles, in order to better serve the construction industry. According to the related concepts in the development of green building design, and combined with practice, this paper briefly analyzes the application of green building concept in housing design. It provides some reference for the development of construction industry.

Under the combined effect of global climate change and local regional environmental change, drought has developed into a natural disaster with high incidence on the earth. As the Yangtze River is the mother river of Chinese civilization, the drought phenomenon in the source area in recent decades has seriously affected and restricted the development of local agriculture and economic society. With the long-term practice of remote sensing technology, researchers have improved drought monitoring methods, including crop water stress index. Crop water stress index (CWSI) is widely used in agricultural drought research based on the principle of heat balance. In this paper, the spatial and temporal characteristics of drought in the Yangtze River source area and its influencing factors were analyzed by using crop drought index method. The CWSI value of the source area of the Yangtze River featured a slightly downward trend from 2001 to 2018. With a strong spatial heterogeneity in distribution, it gradually decreases from west to east. The severest drought occurs in summer and autumn, and the regions that are mostly influenced by temperature are mainly in southwest part and the ones mostly influenced by precipitation are mainly in east part. By analyzing the temporal and spatial distribution characteristics of drought and the correlation of meteorological factors, this paper provides an effective basis for drought prevention and control in the Yangtze River source area, and then promotes the accelerated development of agriculture and economic society in the Yangtze River source area of our country.

Moment method is famous for its calculation efficiency. Moments of the performance function are obtained by point estimates based on Hermite Integration. The reliability index and probability of failure can be obtained using existing standardization function or existing distribution systems. The precision of moment method increases monotonously with the increasing number of estimating points. The performance functions with non-differentiable points are frequently encountered when elasto-plastic behavior dominates for a structure under loading. Thus the accuracy and efficiency of moment method should be addressed for performance functions with non-differentiable points. In this paper, an example of structural performance functions is presented to show the existence of non-differentiable points. Two example performance functions are used to verify the accuracy and efficiency of moment method. The MCS method is employed to obtain the accurate results of probability of failure. The relative errors of probability of failure from moment method are obtained through a comparison with the results from MCS method. The fluctuation of the relative errors with the number of estimate points is also presented. The required number of estimate points for performance functions with non-differentiable points is discussed through the above two examples. Finally, criteria to determine the estimate points for performance functions with non-differentiable points are proposed and verified the applicability.

The occurrence of grouting defect areas in metro concealed excavation tunnels will lead to water seepage or deformation of the tunnels, which in turn will affect the metro operation and the safety of the buildings around the metro. In order to detect the effect of grouting in defective areas of concealed tunnel, this paper introduces the principle and characteristics of seismic scattering technology, and illustrates the application of this technology in detecting the effect of grouting in defective areas of concealed tunnel in Xi'an metro line 6 from Textile City to Textile Road with the application example of seismic scattering technology. The results show that: the grouting area shows high speed anomalies in the wave velocity image, and the defect area shows low speed anomalies, and the location and morphology of the grouting area and the defect area can be determined according to the distribution of high and low wave velocity anomalies in the wave velocity image. The technology also has the features of simple operation, large detection depth and high resolution, which is an effective tool for future urban metro construction and environmental impact detection and evaluation.

Under surge condition, the composite motion of heave, roll, pitch, sway and surge occurs in the concrete mixing vessel, which affects the measurement accuracy of the load cell. Taking the S-shaped load cell as the test object, the measurement accuracy of the load cell under the condition of complex force field is tested by using the six degree of freedom test platform to simulate the medium and long period surge sea conditions. The test results show that: the measured value of the load cell is affected by the sway acceleration, the surge acceleration and the heave acceleration, and is positively correlated with them; when the meaningful wave height is 1m and the average zero crossing period is 6 ∼ 10s, the direct weighing accuracy of the concrete mixing vessel can not meet the requirements of the domestic standard.

According to the construction site monitoring of a subway tunnel shaft in Beijing, the deformation laws of surface settlement, horizontal displacement and vertical displacement of retaining structure during shaft construction were analyzed. The results show that: firstly, the ground settlement around the shaft can be divided into two stages, the rapid settlement stage before the floor construction and the stable settlement stage after the floor construction. The settlement rate and value of the middle point of the long side of the shaft is faster and bigger than the corner point and the middle point of the short side. The settlement value first increases and then decreases with the increase of the distance to the pit side. The maximum settlement is located at (0.61 ∼ 1) times the excavation depth behind the diaphragm wall. Secondly, the horizontal deformation of the long side of diaphragm wall is obviously different from the short side. The horizontal deformation of the long side is larger than the short side, and the position of the maximum horizontal deformation is deeper than the short side. The horizontal deformation curve of the middle point of the long side has obvious inflection point, and the middle point of the short side presents reciprocating type. The variation range of horizontal displacement of diaphragm wall top is between 10 mm, and the maximum horizontal displacement is 0.037% of shaft depth. Finally, the vertical displacement of the top of the diaphragm wall settles rapidly before the excavation of the bottom plate, and the settlement value decreases gradually after the excavation, and the increase rate of the diaphragm wall settlement is the largest when it is excavated to the bottom of the shaft. This deformation law can provide reference for the optimization of support design of similar projects.

The steel-structured corridor project of the Industry Innovation Park (IIP) in Beijing adopts an overhanging design with a large size and span. In the demolition stage of the overhanging support, the steel structures will deform. In order to understand the deformation degree of the steel structures in IIP in real time and ensure construction safety, it is necessary to monitor the deformation process of the steel structures. We select the points sensitive to deformation and key parts of the steel structures as monitoring points, and make an automatic deformation monitoring scheme. We use the deformation monitoring system based on measuring robots and Global Navigation Satellite Systems (GNSS) to monitor the steel structures. Then we compare and analyze the deflection values measured by the two monitoring systems. The results from the two monitoring systems are relatively consistent and mutually verify. The results also show that the steel structures are obviously deformed due to the influence of unloading construction. In addition, deflection values obtained by deformation monitoring are compared with the deformation limit of the key steel components derived from the design code. The results show that the deflection values are within a reasonable range, indicating that the construction design of the steel structures in IIP is reasonable and the steel structures are in safe conditions. The deformation monitoring systems based on measuring robots and GNSS technology used in this paper meet the monitoring requirements in the construction phase and can play their value in similar projects.

Oils are mainly transported by pipe in long distance for its high efficiency. While oil pipe leakage will cause serious social and environmental consequences, e.g. fire even life lost, water and soil pollution. Thus it is important to recognize pipe leakage at initial stage in engineering practice. In this research, a negative pressure wave based detection method was established for pipeline leakage recognition. Suitable parameters of negative pressure wave signals with significant difference for different working conditions were selected. Principal Component Analysis (PCA) method was conducted to reduce the dimensions of the negative pressure wave vector. Self-organizing map (SOM) Neural network was finally adopted to identify the signals for different working conditions. The proposed method was validated by experimental data, which shows that the methodology gives a high recognition rate, which can be referenced in pipe monitoring in engineering practice.

The high-speed railway infrastructure maintenance is the key to ensure the safe operation of the railway. The technical characteristics and advantages of Beidou Navigation Satellite System (BDS), Geographic Information System (GIS), and Remote Sensing (RS) are analysed for integrated application based on the practical application of professional engineering infrastructure monitoring, equipment inspection, disaster prevention and warning, workers management and time synchronization, and the solution of intelligent monitoring system for high-speed railway infrastructure maintenance was proposed. And this system supports visual display of vector and electronic map, status query of workers, trains, equipment and infrastructure for remotely monitoring, detecting and managing, which can provide low-cost, reliable and accurate information services for the security monitoring and management of the high-speed railway infrastructure maintenance.