箱梁大体积混凝土水化热效应与开裂风险分析OACHSSCD

The thermal effect resulting from hydration heat is the primary cause of cracking in mass concrete for box girder during construction.To thoroughly investigate the time-dependent thermal effect and cracking risk of mass concrete in box girder during the hydration reaction process,this study conducted systematic temperature monitoring of the mass concrete in the Segment No.0 by em-bedding temperature sensors within the box girder structure.By integrating the temperature monitoring data with finite element simulation results,the temperature rise curves,temperature difference curves,and spatial distribution characteristics of the temperature field at critical measurement points within the mass concrete of the box girder were obtained.The results indicated that the temperature of the mass concrete in the box girder peaked at 79.5 ℃ at 60 hours after pouring,with the maximum temperature differences in the longitudinal,transverse,and vertical directions of the bridge being 44.1 ℃,41.7 ℃,and 44.7 ℃,respectively.Finally,based on the measured data and finite element simulation results,a calculation formula for vertical temperature difference distribution and a hydra-tion-induced thermal damage computation model were developed for mass concrete box girders.The findings of this study provide a valuable reference for assessing hydration heat effects and cracking risks in similar mass concrete box girders.