节段预制箱梁后浇横隔墙的水化热效应分析

摘要

Hydration heat effect induced by construction of post-casting diaphragm in segmental precast box-girder was studied combining with practical engineering. The model was founded with finite element software ANSYS. Based on the theory of three-dimensional transient temperature field, the hydration heat effect was simulated. The distribution and variation with time of the temperature field and the stress field of box-girder were analyzed. The law that the outer of web was under tension and the inner of web was under compression due to thermal stress caused by hydration heat, and the region of peak value of tensile stress were reveled, and the easy crack position was pointed out. The influences of laws and degrees of cement varieties, admixture proportions and casting temperatures on stress field were analyzed. The results show that the influence of cement variety on hydration heat effect is greatest, that of admixture proportion is the greater, and that of casting temperature is the smallest.%结合某实桥工程背景,对节段预制箱梁进行后浇横隔墙施工过程的水化热效应进行了研究,使用有限元软件ANSYS建模,根据三维瞬态温度场理论,进行了水化热效应的仿真模拟,分析了箱体温度场和应力场的分布及随时间变化情况,揭示了水化热温度应力使预制箱体腹板外表面受拉、内侧受压的规律及峰值拉应力区域,指出容易开裂的位置；分析了水泥品种、混合材料用量、入模温度3个参数对应力场的影响规律及影响程度.结果表明:水泥品种对水化热效应的影响最大,其次是混合材料用量的影响,入模温度对水化热效应的影响最小.