电站尾水渠施工期渗流场数值分析

为研究施工期尾水渠基础渗流场、渗流稳定以及渗流量等问题,选取电站尾水渠典型断面,建立尾水渠岩土体渗流的数学模型,结合电站尾水渠典型断面确定边界条件,利用伽辽金有限元方程进行数值计算,对尾水渠施工期渗流场进行模拟.结果表明:塑性混凝土防渗墙设计效果较好,渗流量的绝大部分通过防渗墙以下入渗,降低了孔隙水压力;在渗流出溢处水力坡降超出允许水力坡降,该处需采取工程措施,以免发生渗透破坏.这些成果可为施工期尾水渠安全运行提供理论根据.

Numerical Simulation of Seepage Field of Hydropower Station Tailwater Channel in Construction Period

In order to study problems of seepage field,seepage stability and seepage quantity,the classic section of tailwater channel was firstly selected to build the methematic model of rock and soil seepage.Secondly,the boundery conditions of classic section were determined.Finally,the seepage field in construction period was simulated by means of Galerkin Finite Element Method.Therefore,some conclusions were drawn,plastic concrete seepage-prevention walls worked well and the majority of seepage quantity infiltrate below the walls which reduced the pore water pressure very much;the hydraulic gradient of the channel slope where the seepage spilled out exceeded the allowable value,so some engineering measures should be needed to avoid seepage damage.These achievements could provide references for safe operation of tailwater channel in its construction period.