任意滑动面搜索新方法应用于三维复杂土坡稳定性分析

Application of new method of arbitrary sliding surface search to stability analysis of complex three-dimensional slopes

在提出任意三维滑动面搜索方法的基础上,针对滑动体非对称情况(包括准线不对称和长度不对称)、母线不在滑动体内沿滑动方向断面尺寸最大的面上、土坡含软弱夹层的情况,采取了一些解决措施,并将其应用于工程上常见的填挖方复合土坡、水平分层填方路堤、公路纵断面为平斜坡的土坡和含软弱夹层的土坡这4种算例中。分析表明:①此方法可以对一些较复杂条件下的土坡进行稳定性分析,并能够寻找到较优的最危险滑动面(包括整体和局部稳定性);②当填挖边坡上填方段和挖方段的材料不一致时,更容易在抗滑稳定性差的材料处发生失稳,但当填方段和挖方段的材料重度γ相同时,两种材料的φ/c是否相等在一定程度上对滑动体的对称性和大小有影响;③对于公路纵断面为平斜坡的土坡,其潜在最危险滑动面更倾向于平坡段,斜坡对边坡的稳定系数有一定的积极影响;④在含软弱夹层的土坡中,当滑动体的长度无限长时,其三维稳定性趋于二维稳定性,与以往研究成果相比较时,得出本文方法计算出的结果与之非常接近,说明本文方法可行。

Based on the proposed arbitrary three-dimensional sliding surface search,for the sliding body of asymmetry（including the case of asymmetry of standard line and asymmetry of length）,mother line being not in the largest cross-section of the sliding body along the sliding direction and slopes with weak interlayer,some solution measures are used.Then they are applied to four examples in the engineering：common excavation and filling compound slope,filling embankment at form of hierarchical level,vertical section of road with flat and oblique slope and the slope with weak interlayer.Analysis shows that：firstly,this method can be employed to analyze stability of some slopes under complex conditions and to find the optimization of the most dangerous sliding surface（including the general and partial stability）;secondly,when the fill and excavation materials are inconsistent in excavation and filling compound slope,the sliding instability occurs more easily at poor stability of materials,but in the case of filling and excavation materials with the same severe γ,whether or not φ/c of the two materials is equal impacts symmetry and size of the sliding body on a certain extent;thirdly,for the slope of vertical section of road with flat slope,the most dangerous sliding surface is more inclined to flat slope section of the slope,and oblique slope section of the slope has some positive impact on the slope stability;fourthly,in the slope with weak interlayer,when the length of sliding body reaches infinite length,its three-dimensional stability tends to two-dimensional stability,and the results from this method are very close when compared with the previous results of other methods,so it shows that this method is feasible.