渗透动水压力对坝基双斜面深层抗滑稳定的影响分析

摘要

Running of reservoir in high water level will result in a great value of seepage hydro-dynamic pressure moving though fissures in dam foundation. Based on method of constant safe factor, the paper analyzes the relations between hydrodynamic pressure on the double slip surface and stability of dam considering low penetrability rock mass on dam foundation. The calculating results show that hydrodynamic pressure on slip surfaces has little role to play in the lowdown anti-slip safe factor when reservoir runs at a certain water level. So the hydrodynamic pressure acted on the surface of seepage tunnels in dam foundation rock mass can be neglected in calculating deep anti-slip stability of concrete dam. Moreover, the different discharge for components of both anti -slip and slip forces will figure up a different value of safe factor and then come to a different evaluation result. So the study may provide theoretic references for improving the rigid body limit equilibrium method.%大坝高水位蓄水运行期间,坝基渗流通道中会出现很大的渗透动水压力.本研究对坝基岩块透水性低的双斜面深层滑动情况,用等安全系数法,分析了滑动面上的动水压力对坝基稳定的影响.计算结果显示,蓄水位一定时,双滑动面上的动水压力对降低抗滑稳定安全系数的影响很小,稳定分析时可以忽略动水压力.分析中还发现,从不同的角度对抗滑力和滑动力组成做不同的处理,会出现不同的稳定性评判结果.基于此结果,本研究可为进一步完善刚体极限平衡法提供理论参考.