Analysis of the Construction Machinery Work Efficiency as a Factor of the Earthworks Sustainability

Being aware of the construction machinery work efficiency is one of the key conditions of dynamic planning of machine work at the construction site and it can be considered as one of the earthworks sustainability factors. The main topic of this paper is the time study analysis of one standard technological cyclic construction machine process (the excavators' loading the transportation vehicle), which was observed on-and-off site and analysed. On-site data was obtained by snapback chronometry method with the purpose of determining actual work efficiency; while the (off-site) planned work efficiency was determined using the standardized tables. The aim was to determine the existence of a deviation and examine the differences between planned and actual work efficiency of particular technological process in earthworks as well as to identify its cost-effective area as a prerequisite for identifying the earthworks sustainability. As the earthworks sustainability is the synthesis and concordance of beneficial activities for technological, economic, environmental and social performance context, the balance of excavators' work efficiency is needed. It was concluded that in order to achieve sustainability, i.e. to be in cost-effective area, the maximum value of excavators' cycle time extends up to 50 seconds.