Numerical calculation of bridge temperature considering all-weather conditions

Abstract

Temperature is one of the critical environmental factors affecting bridges’ performance. Accurate temperature distribution is essential for reliable structural condition assessment. Existing studies have predominantly focused on the most adverse thermal conditions under clear skies, but seldom considered the cloudy or rainy conditions, which may not reflect the actual scenario of the bridges in real-time structural monitoring. This study develops a numerical method to calculate the bridge temperature distribution under all-weather conditions, including sunny, cloudy, rainy, and snowy scenarios. According to the illuminance and cloud cover, real-time solar radiation correction models are employed to quantify the shielding effect of clouds on solar radiation during cloudy or rainy weather. These models, combined with other meteorological parameters such as air temperature and wind speed, enable accurate determination of thermal boundary conditions for refined heat-transfer analysis. An automatic computational framework is strategically developed for weather scenario classification, boundary condition determination, and heat-transfer analysis. The proposed framework is applied to three scenarios: An experimental reinforced concrete slab, a practical steel box girder suspension bridge, and a real concrete box girder continuous bridge. Results demonstrate that the proposed correction models significantly enhance the heat-transfer analysis accuracy under various weather conditions. A good agreement has been achieved between simulated and measured temperatures across girder sections with different materials and geometries, thereby verifying the effectiveness of the proposed method. This study establishes a theoretical foundation and practical framework for investigating bridge temperature behaviors under complex weather conditions.