沥青混凝土心墙石渣坝水位降落期上游坝坡稳定分析

The Core Dam of Asphalt Concrete Stability Analysis of Upstream Dam during Waterline Dropping

近些年来四川地区新建了很多沥青混凝土心墙石渣坝,该坝型与传统意义上土石坝有所不同,其防渗体为沥青心墙,厚度约为水头的1%,根据坝的分区设计,一般将弱风化砂岩料放置于坝上游湿润区,其作用是大坝上游水位变化时可以快速排出坝体内孔隙水;将强风化砂岩料及泥岩料放置于大坝下干燥区,其作用是保持起到压重作用,靠重力维持大坝稳定。本文在理论分析大坝上游水位变化时浸润线变化规律的基础上,通过计算实例提出了川内地区该种类型大坝水位降落时上游坝坡抗滑稳定安全系数变化规律,对此类坝型的设计有指导意义。

These years,many core dams of asphalt concrete are being built in Sichuan province,which are different from traditional earth rockfill dams.Their anti-seepage body are asphalt core dams with 1%thick of water head.According to distribution design of the dam,moderate weathering sandstones are placed at humid area of upstream dam area,so as to ensure good drainage for inner hole water of the dam while its waterline changes.At the same time,intense weathering sandstones and mud rocks are located at drying area of downstream dam zone to keep the dam stable by gravity.When waterline of the upstream dam changes,phreatic line varies too.Their variation regulations were theoretically analyzed in this thesis.Furthermore,change rules of anti-skid safety for the same type of upstream dams during waterline dropping were offered by calculating living examples in Sichuan province.The thesis presents important references for dams design of this type.