管道衬砌内水外渗对边坡稳定影响的数值模拟

根据钢筋混凝土受拉开裂特性，通过混凝土开裂后钢筋和混凝土联合承载原理，提出了在内水压作用下混凝土衬砌开裂的裂缝宽度估算公式。根据开裂衬砌内水外渗的规律，提出了高压管道内水外渗与混凝土衬砌裂缝宽度相互影响的有限元迭代计算分析方法。该方法将内水压荷载分解为起裂荷载和破坏荷载，对混凝土衬砌起裂荷载采用一次加载，对破坏荷载采用分级加载迭代，由此较好地反映衬砌开裂和渗流耦合作用效应。根据渗流荷载对边坡的破坏作用，提出了对边坡稳定判断的思路。通过对实际工程的分析计算，论证了高压管道内水外渗对边坡的稳定影响, 为内水外渗与应力场耦合分析提供了一种有效的计算方法。

Numerical analysis of infiucence of seepage from underground conduit lining under high internal water pressure on slope stability

According to the failure features of concrete lining under seepage load,a three-dimensional numerical coupling analysis of seepage field and stress field is made on the fracture regulation of the high pressure conduit lining.Based on cracking characters of concrete lining,the computation formulae of crack width for concrete lining under seepage load are given.According to the bearing capacities of the concrete lining at the instant of cracking,the seepage load can be divided into two parts during computation.The preceding part of the load,smaller than that critical load,can be applied to the concrete lining structure once;and the latter part which is larger than the critical value adopts gradient iterative method.By this way,the rock slope stability taking into account seepage interaction effects can be analyzed preferably.Through computing practical engineering,the infection of seepage induced by high pressure water inside conduit is demonstrated.An efficient computation method is provided for the design of underground conduit with high internal water pressure.