诸暨市安华水库大坝渗流安全评价

Seepage Safety Evaluation of Anhua Reservoir Dam in Zhuji City

针对安华水库防洪滞洪功能、常蓄水位低特点和测压管仅布设于坝顶及下游坡情况,根据常蓄水位时的渗流实测资料推算黏土斜墙前后位势差以及高水位(设计、校核)状态下的渗透比降,综合评价大坝渗流安全性。分析结果表明,大坝黏土斜墙后侧渗压水位比较稳定,相对上游库水位,黏土斜墙下游侧水头削减超过70%,黏土斜墙防渗效果较好,大坝与泄洪闸翼墙连接段防渗效果较好;黏土斜墙、坝体砂砾石渗透比降满足规范要求,大坝渗流状态总体安全。

In view of the flood control and detention function of Anhua Reservoir,the characteristics of low constant water level and the fact that the pressure measuring pipes were only laid on the crest and downstream slope of the dam,this paper calculated and analyzed the potential difference between the front and back of the inclined clay wall and the seepage gradient under the condition of high water level(design and check working conditions)according to the measured seepage data of the constant water level,and comprehensively evaluated the seepage safety of the dam.The results show that the seepage pressure water level at the back of the inclined wall of the dam is relatively stable;the water head of the lower side of the inclined wall of the dam is reduced by more than 70%compared with the water level of the upstream reservoir;the anti-seepage effect of the inclined clay wall is good;and the anti-seepage effect of the joint section between the dam and the spillway gate is good.The permeability gradient of clay inclined wall and sand gravel in dam body can meet the standard requirements,and the seepage state of dam is generally safe.