考虑水化热粘弹性应力影响的超长结构设计计算与分析

超长结构因水化热与日光曝晒的环境影响,在结构的受力构件内产生不均匀的变形,当边界支座受到强烈约束时,可使结构产生随混凝土硬化龄期变化的附加内力。按照设计规范的技术发展水平,计算考虑水化热对结构的影响有很大的难度,当结构形状较复杂时尤为如此。以此为研究重点,采用粘弹性有限元数值分析方法,摸拟了水化热对超长结构的影响,可以得到结构使用前的应力状态和对承载力的影响,直接判断混凝土控制截面处是否存在开裂及发生破坏,在设计和施工中得到控制和避免。

DESIGN CALCULATION AND ANALYSIS OF LONG STRUCTURE CONSIDERING THE EFFECTS OF VISCO-ELASTIC STRESSES OF HYDRATION HEAT

Additional internal forces, which vary with hardening age of concrete, are induced in long concrete structures by hydration heat during construction and air temperature change if the expansion and shrinkage are restricted at boundaries. It’s difficult to consider the effects of cement hydration heat for structure members, according to the present design code, especially while the shape of structure is complex. In this paper, the effects of hydration heat on long structure members are simulated by visco-elastic finite element method. The stress states and bearing-capacity in main girder of frame structure can be obtained before subjected to load. The crack and damage at control sections of concrete members can be analyzed.