Numerical Investigation of Factors Affecting Early-age Cracking in Precast Concrete T-Beams During Storage Under Large Daily Temperature Differences

抄録

Precast concrete T-beams often develop early-age cracking during storage due to large daily temperature differences, threatening the long-term durability of bridges. To investigate the factors leading to cracking, this study establishes a coupled thermal-mechanical model that accounts for heat of hydration, thermal exchange, solar radiation, concrete shrinkage, and creep. Based on this model, the effects of curing method and formwork removal timing on the cracking risk of T-beams were analyzed. The results indicate that the use of steel formwork + PU insulation board and full shading measures can effectively mitigate the impact of temperature differences and radiation on thermal stresses generated in precast concrete T-beam. The simulated stress patterns closely match field observations, confirming the model’s reliability. This study provides valuable guidance for cracking prevention and optimized curing strategies for precast concrete T-beams in regions with large daily temperature differences.