Steel box girders, a fundamental component in modern bridge construction, experience complex thermal behavior under solar radiation that significantly impacts their structural performance.
This study examines temperature distribution patterns in scaled steel box girder models using controlled radiation angles to simulate varying solar exposure conditions. Through experimental testing of three scaled models with different geometric parameters, temperature fields were measured using thermistors and thermal imaging techniques.
The results reveal that beam width predominantly affects vertical temperature gradients, with wider sections experiencing temperature differentials up to 8.2 °C. Beam height primarily influences lateral temperature gradients, particularly at higher radiation angles, generating temperature differences up to 6.8 °C.
Computational validation using COMSOL finite element software enabled the development of a predictive model for vertical temperature field distribution. These findings advance the understanding of thermal behavior in steel box girders and provide a quantitative basis for evaluating temperature-induced stresses in bridge design under various environmental conditions.
