陆浑灌区填方坝整体稳定分析

Slope stability analysis of earth dams of Luhun irrigation engineering

陆浑灌区是我省西部的大型灌区,运行以来在农业生产及抗旱斗争中发挥巨大作用,但灌区的数百座填方坝施工质量较差,整体和局部稳定都存在一些问题。针对填方坝的整体稳定,采用条分法计算填方坝在无水、低水位输水和高水位输水三种务件下的稳定安全系数。经大量渗流计算和稳定分析,认为部分填方坝不能满足稳定要求:坝体渗流使安全系数下降30％左右;改善填方坝整体稳定的措施以渠道防渗、堤坝背坡面排水、增加坝体密实度为最佳,可由具体条件选择。同时这些措施对坝体的局部稳定也是有利的。

Luhun irrigation engineering is one of the biggest in the west part of Henan province. It has brought into play the enormous effect in the past twenty years. But accident took place repeatedly because its earth dams are of poor quality. Its local stability and slope stability are not satisfied. In this paper, the safety coefficients of slope stability under seepage flow are calculated by means of slice method. By a vast amount of computation of seepage flow and computation of slope sliding, it is illustrated that the slope stability of the part of earth dams are not content, seepage flow reduce safety coefficient, seepage control measures to increase stability of resisting sliding include preventing seepage flow of channel, draining away water of slope and increasing density of dams. At the same time the measures are of advantage to the local stability of earth dams.