Long-Term Monitoring of Temperature Differences in a Steel Truss Bridge with Two-Layer Decks Compared with Bridge Codes: Case Study

Abstract

Bridge structures are subjected to environmental thermal actions, which cause a complex temperature field in bridge structures. This research carried out long-term monitoring of temperature differences in a steel truss bridge with two-layer decks. Big temperature differences existing in the steel truss were revealed and explained using the influence factors of solar motion and two-layer deck shading. The monitoring results show that some temperature differences were notably higher than the specified values in current bridge codes, so appropriate temperature differences for thermal action design were evaluated through probability statistics analysis. The research results show that deck coverage plays an important role in the variation of temperature differences, and there is a big difference between the temperature differences with or without deck shading. Our suggestion is that various types of deck shading should be categorized for more accurate thermal action design in current bridge codes. The steel truss member designed with enough deck coverage can effectively decrease thermal actions. The results of this research will provide meaningful information for thermal action design of steel truss bridges with two-layer deck coverage.