基于温度应力仿真的碾压混凝土拱坝诱导缝开裂分析研究

诱导缝作为碾压混凝土拱坝结构防裂措施,能否在坝体温度下降时率先开裂,以消散温度应力,是控制坝体温度裂缝的关键。应用大型有限元分析软件ANSYS,采用薄层实体接缝单元模拟诱导缝,考虑施工期至运行期全过程瞬态温度荷载,通过三维有限元温度应力仿真分析和诱导缝开裂情况分析对全部采用"诱导缝"分缝形式的某碾压混凝土拱坝进行可行性研究。结果表明:坝体高拉应力区设置的诱导缝,在做好缝端处理,消除诱导缝与地基接触部位应力集中的条件下,能够有效地释放坝体应力,保证坝体在温度荷载下的运行安全。仿真分析结果可为该碾压混凝土拱坝的温度控制、裂缝预测及其预防提供参考依据。

Research on induced joints cracking analysis of RCC arch dam based on temperature stress simulation

As a structural anti-cracking measure of the rotter compacted concrete(RCC) arch dam, whether the induced joints can crack firstly to reduce the temperature stress when the temperature of the dam drops is the key to control the temperature crack of the dam. The large finite element analysis software ANSYS and the thin-layer solid joint unit were to simulate the induced joint. Considering temperature load from construction period to operation period, the three-dimensional finite element temperature stress simulation analysis and the induced joint cracking analysis are all adopted to study the feasibility of a RCC arch dam in the form of induced joints. The results indicate that induced joints set in high tension stress area could effectively release the temperature stress of the dam and ensure the safety of the dam under the temperature load when the stress concentration of the contact parts between the induced joints and the foundation is eliminated. The simulation analysis results can provide reference for the temperature control, crack prediction and prevention of the RCC arch dam.