三峡工程水电站厂坝间压力钢管取消伸缩节研究

Study on penstocks without expansion joint between dam and powerhouse in Three Gorges Project

为论证三峡水电站厂坝间压力钢管取消伸缩节的可行性,本文在左岸岸坡和河床部位各选取一台机组为研究对象,将大坝、厂房和压力钢管作为整体进行模拟厂房混凝土施工过程的三维有限元仿真计算,重点分析了不同季节合拢情况下用以代替厂坝间压力钢管伸缩节的10m长度垫层管的变形和应力,并对若干影响因素进行了敏感性分析。结果表明,岸坡坝段可以取消伸缩节,而河床坝段取消伸缩节是有条件的;夏季合拢比冬季合拢对垫层管应力有利。

A numerical simulation by adopting a 3D FEM model was carried out for analyzing the deformation and stress of a 10m long steel penstock wrapped in soft gasket. The feasibility of eliminating expansion joint between dam and powerhouse in Three Gorges Project was discussed. One of the penstocks in left bank slope and another in the riverbed were studied in different seasons of closure. The penstock, dam and powerhouse were included in the model and the concrete placing process was simulated. A sensitivity analysis of some computational conditions was made. The results indicate that the penstocks in the left bank slope can be constructed without the expansion joint, but those in the riverbed are conditional. Closure in summer is more favorable for the penstock stress than closure in winter.