Solar-induced thermal effects on steel-concrete composite beams: A meteorological data-driven analysis for long-span bridges

To investigate the effects of solar radiation temperature on steel-concrete composite beams in long-span bridges, a temperature analysis method based on meteorological parameters is proposed. First, an accurate thermal analysis model was established based on the principles of heat conduction and finite element computation theory. The model’s accuracy was validated using measured data. Subsequently, the representative values of temperature differences for the composite beam were calculated based on the analysis of historical meteorological data. The calculation method integrated the finite element temperature field model with the generalized extreme value distribution function. Finally, the simulated solar radiation temperature field was applied to the overall finite element model of the long-span bridge. The comprehensive influence of solar radiation temperature effects on long-span bridges was then evaluated. The results indicate that the finite element analysis results are in good agreement with the measured values. The 50-year return period representative value (T_d) for the maximum vertical positive temperature difference in the composite beam is 17.613 °C. The compressive stress induced in the concrete bridge deck of the composite beam by temperature loads during the operational phase exceeds twice that caused by lane loads. By analyzing seven different load effect combinations, the impact of the most unfavorable load effect combination on the bridge structure was determined. This provides an important reference for bridge design and assessment. This research offers a novel method for understanding and predicting the temperature response of long-span bridges. Additionally, it provides theoretical foundations and technical support for achieving the lightweight goals of bridge health monitoring.