Temperature Records in Concrete Box-Girder Segment Subjected to Solar Radiation and Air Temperature Changes

This paper presents the experimental results of a full-scale concrete box-girder segment subjected to ambient thermal loads. The experimental segment was instrumented with 62 thermocouples to measure the concrete temperatures in different locations and a weather station to measure air temperature, wind speed, and solar radiation. The records from the different sensors were collected for more than one year at time intervals of 30 minutes. The full one-year records showed that the maximum vertical temperature gradient was occurred in June and was approximately 20 °C, while the maximum lateral temperature gradient was occurred in December and was 19 °C. Finally, a vertical temperature gradient model, which composes of three multi-linear parts, was proposed. The resulted temperature distributions, stresses, and deflection from the proposed model were closer to those of the experimental gradient compared to the AASHTO's and the NZ Bridge Manual's gradient models.