摘要
目前分析堆石坝下游坡的抗震稳定性仍采用瑞典圆弧法和简化毕肖普法,土体的抗剪强度多用莫尔-库仑准则。试验表明堆石材料的抗剪强度更符合非线性表达式。已有文献采用非线性抗剪强度分析堆石坝的抗震稳定性,但该方法的安全标准少见论证。本文对采用线性与非线性抗剪强度的有限元法和极限平衡法分析堆石坝坝坡稳定性进行了比较。结果显示,毕肖普法安全系数比瑞典法高2%～10%,采用非线性抗剪强度计算的安全系数比采用线性抗剪强度高15%～25%。与毕肖普法容许安全系数比瑞典法高同理,用非线性抗剪强度准则进行堆石坝坝坡稳定计算,其容许安全系数也应在线性准则的基础上提高。提高的幅度有待进一步积累经验。
The Sweden circular method and the Bishop simplified method were used commonly on seismic stability analysis of rockfill dam slope. The shear strength of the soil is originally expressed by MohrCoulomb failure criterion as a linear function. But many tests show the shear strength of the rockfill material is a nonlinear function of the normal stress. Some papers have analyzed the seismic stability of the rockfill dam slope by the nonlinear shear strength of the rockfill material. But the suited safety factor criterion was not clarified. In this paper, stability safety factors of the rockfill dam slope are compared by finite element method and limiting equilibrium method by the use of linear and nonlinear shear strength. The result shows the safety factor of Bishop method is larger 2%～10% than Sweden circular method, and factor of nonlinear shear strength is larger 15%～25% than linear. So the safety factor criterion of nonlinear shear strength should larger than linear.
出处
《世界地震工程》
CSCD
2002年第4期11-17,共7页
World Earthquake Engineering
关键词
坝坡
抗震稳定分析
堆石坝
非线性抗剪强度
rockfill dam
seismic stability analysis
nonlinear shear strength
