高桩码头岸坡滑弧模式研究与变形稳定性分析

分别采用有限元强度折减法、简单条分法以及Spencer法对108组不同条件的高桩码头岸坡进行了整体稳定性分析，比较了上述3种方法计算结果的差异性与关联性，并依据有限元强度折减法系统地研究了不同岸坡滑弧模式发生的土体强度条件，分析了岸坡特征点的侧向位移随安全系数的变化关系。结果表明，有限元强度折减法与简单条分法在安全系数的定义形式上是一致的，但计算结果一般存在-1%～8%的差异；当坡体下方或后方的土体与坡体的强度指标之比小于某临界值（一般在1～2之间）时，滑弧将向深处或者码头后方扩展；而当岸坡的整体稳定安全系数接近工程规范所规定的安全阈值时，坡顶点的侧向位移一般会出现突变。最后，通过对某工程岸坡实例加固效果的分析，验证了结论的合理性和有效性。

Research on slip arc mode and deformation stability of bank slope on high-piled wharf

The strength reduction finite element method, the Swedish slices method and Spencer’s generalized procedure of slices are adopted to analyze the global stability of bank slops on high-piled wharves under 108 different conditions. The results are compared to demonstrate the difference and relevance among three methods. The soil strength conditions when different slip arc modes occurred are studied with the strength reduction FEM. Meanwhile, the dependence of the lateral displacement of the feature points on the safety factor is analyzed. It was indicated that there is a difference of -1%~8% between the results of the strength reduction FEM and the Swedish slices method, though the definitions of safety factor of two methods have the same form. It also demonstrated that when the ratio of the soil strength under or behind the slope body to that of the slope is less than a certain critical value usually between 1 and 2, the slip arc will expand to a deeper position or the rear of the wharf, from which we draw a conclusion that when the safety factor comes close to the safety threshold defined by the engineering standard, there will be a drastic change in the lateral displacement. In the end, the conclusion is proved to be reasonable and efficacious by a practical project.