全埋式钢衬钢筋混凝土管道与坝内垫层管比较分析

结合某坝后式水电站工程实例,对全埋式钢衬钢筋混凝土管道方案进行了平面非线性有限元分析,比较了不同管坝接缝面连接形式(垫层、冷缝、固结)对结构受力特性的影响.计算结果表明:垫层接缝方案可以有效地减少内水压力传至坝体,冷缝连接方案次之,固结方案最为不利,因此从坝体安全性角度考虑,建议在工程中使用垫层接缝方案.在坝址区域地震烈度较高或者对管、坝混凝土开裂有严格控制的工程中,建议使用坝内垫层管方案,这样不仅可以保证坝体及管道抗震安全,又能使钢管承担更多的内水压力,减少或避免管道及坝体混凝土开裂.

Comparative analysis of steel lined reinforced concrete penstock all embedded in dam and dam-embedded steel penstock encircled by cushion layer

A plane nonlinear finite element analysis of steel lined reinforced concrete penstock all embedded in dam was made in combination with practice of a hydropower station at the toe of dam.The different connecting modes between penstock and dam which consist of cushion layer filled in the rabbet,bed joint and project of consolidation were mainly focused in the comparison analysis of stressing characteristics of construction.The calculation results indicate that the mode with cushion layer filled in the rabbet can effectively reduce propotion of internal water pressure introducing to dam body;the mode with bed joint takes the second place and the suboptimal project is consolidation.From the standpoint of safety of dam,the mode with cushion layer is suggested in engineering.Otherwise,the proposal of dam-embedded steel penstock encircled by cushion layer is suggested in engineering with high seismic intensity in dam site or that in which there is strict control in concrete cracking around steel penstock.It can make steel liner take more internal water pressure in order to avoid concrete cracking on the basis of guaranteeing the seismic behavior of penstock and dam body.