基于ANSYS的零号块大体积混凝土水化热分析

Temperature field and stress analysis of hydration heat of zero block mass concrete based on ANSYS

针对大体积混凝土在施工过程中由于水化热引起的开裂及应力超限难题,采用有限元分析方法对箱梁零号块大体积混凝土水化热进行分析研究。以阜淮铁路跨青阜铁路(72+72)m预应力混凝土T构连续梁桥为工程依托,首先利用ANSYS有限元软件建立该桥梁的零号块模型,分别建立有无冷却水管条件下的温度场和应力场有限元模型,并对该零号块浇筑期间的水化热及应力进行分析。结果表明,在无冷却水管条件下,混凝土温度达到60.8233℃,局部最大拉应力到达2.07 MPa,而考虑冷却水管的条件下,温度下降到46.6632℃,局部最大拉应力下降到1.47 MPa,满足工程实际要求。该研究为此类型桥梁的零号块混凝土浇筑施工提供重要参考。

In order to solve the problem of cracking and stress overlimit caused by hydration heat in the construction process of mass concrete,the hydration heat of box girder zero block mass concrete is analyzed by finite element method.Based on the project of Fuhuai Railway across Qingfu Railway(72+72)m prestressed concrete T-structure continuous beam bridge,the zero block model of the bridge was established by using ANSYS finite element software,and the finite element models of temperature field and stress field with or without cooling water pipe were respectively established,and the hydration heat and stress during the zero block pouring were analyzed.The results show that under the condition of no cooling water pipe,the temperature of concrete reaches 60.8233℃and the local maximum tensile stress reaches 2.07 MPa,while under the condition of cooling water pipe,the temperature drops to 46.6632℃and the local maximum tensile stress drops to 1.47 MPa,which meets the actual requirements of the project.This study provides an important reference for the construction of zero block concrete for this type of bridge.