大体积混凝土结构温度效应及收缩应力精细有限元分析

摘要

为了研究大体积混混凝土结构的温度效应及温度收缩应力，结合武汉市某住宅楼工程筏板基础底板，运用有限元软件ANSYS对三维瞬态温度场及温度收缩应力进行数值模拟分析，分别模拟了武汉市冬夏季该筏板基础底板的瞬态温度场及温度收缩应力，以及不同厚度的混凝土筏板基础在混凝土浇筑过程中冬夏季混凝土开裂情况。结果表明：冬季混凝土浇筑第四天，混凝土筏板基础上表面混凝土主拉应力大于混凝土抗拉强度，导致混凝土开裂；夏季混凝土筏板基础由于混凝土表面最大主拉应力小于混凝土抗拉强度，混凝土不会开裂。%In order to study the structure of massive concrete temperature effects and temperature shrinkage stress , combining the raft foundation slab of a residential building project in Wuhan,we used the finite element software ANSYS to analysis dimensional transient temperature field and thermal shrinkage stress,and simulated the transient temperature field and thermal shrinkage stress of the raft foundation slab during summer and winter in Wuhan and different thickness of the concrete raft foundation in concrete pouring concrete cracking during winter and summer. The result indicates that the upper surface of the concrete raft foundation concrete principal tensile stress is greater than the tensile strength of concrete during the pouring concrete on the fourth day in winter ,thus causing concrete cracking;while the summer of concrete raft foundation concrete surface maximum principal tensile stress is less than the tensile strength of concrete,thus it would not cause concrete cracking.