土工膜缺陷对土石坝渗流特性及坝坡稳定的影响  

Influence of geomembrane defects in earth-rock dam with different geomembrane layouts on seepage property and dam safety

作　　者：岑威钧[1] 王辉[1] 李邓军 CEN Weijun;WANG Hui;LI Dengjun(College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学水利水电学院

出　　处：《武汉大学学报（工学版）》2018年第7期589-595,共7页Engineering Journal of Wuhan University

基　　金：江苏省自然科学基金项目(编号:BK20141418);国家自然科学基金项目(编号:51679073);江苏高校优势学科建设工程资助项目(编号:YS11001)

摘　　要：采用饱和-非饱和渗流有限元理论,对一坝高30m的典型土石坝分别开展土工膜坝面和心墙防渗时大坝渗流场计算分析,重点考察土工膜缺陷高程和缺陷尺寸对大坝浸润线及渗流量的影响规律,进而对上下游坝坡进行稳定分析.计算结果表明：1）大坝采用坝面或心墙土工膜防渗时,坝内浸润线总体较低,膜后浸润线高度随土工膜缺陷高度呈先增加后减小的局部变化规律.2）土工膜坝面防渗时大坝渗流量随土工膜缺陷高度增加呈先小幅增加后减小的变化特性,土工膜心墙防渗时渗流量随缺陷高度增加而单调减小,渗流量变幅均在2倍之内.3）土工膜缺陷高度对大坝上下游坝坡的抗滑稳定安全系数影响较小.The saturated-unsaturated seepage finite element theory is employed to analyze the seepage field of a 30 mhigh typical earth-rock dam with dam face or core seepage control;with emphasis on the influence on the phreatic line distribution and seepage flux by the height of geomembrane defect and size.Furthermore;the stability of upstream and downstream dam slope are investigated.The results indicate：（1）When the dam upstream surface or core is placed by geomembrane;the height of phreatic line increases at first and then decreases by the increasing of height of geomembrane defect.（2）When the geomembrane is installed on the upstream dam face;the dam seepage flux increases at first and then decreases by the increasing of the height of geomembrane defect.When the geomembrane is installed in the dam core;the dam seepage flux monotonically decreases by the increasing of the height of geomembrane defect.The change of flux is in two times fluctuation.（3）Different height of geomembrane defect has limited influence on the safety factors of upstream and downstream dam slopes.

关 键 词：土工膜缺陷 坝面防渗 心墙防渗 渗流特性 坝坡稳定性 

分 类 号：TV31[水利工程—水工结构工程]