基于应力场的土坡临界滑动面的遗传算法搜索

为快速而准确地评价复杂土坡抗滑稳定性状,采用非线性有限元法分析土坡的应力场,根据应力场定义和计算土坡的稳定安全系数,再将安全系数与遗传算法的适应度函数相联系,从而利用遗传算法优化技术搜索土坡内对应最小安全系数的临界滑动面。给出了遗传算法搜索中的滑动面基因表达、适应度函数、滑动面形状合理性约束等关键实施技术。通过经典算例分析,证明这种基于应力场的临界滑动面遗传算法搜索方法具有可行性、高效性和鲁棒性。

Genetic algorithm for searching for critical slip surface in soil slopes based on stress fields

In order to make a rapid and accurate evaluation of the anti-slip stability behaviour of complicated soil slopes, a nonlinear finite element method was employed to analyze the stress fields in soil slopes, and the factor of safety against sliding was defined and calculated based on the stress fields. The fitness function in the genetic algorithm was linked to the factor of safety while the critical slip surface corresponding to the minimum factor of safety was allocated with the genetic algorithm optimization method. The key techniques in the genetic algorithm include the genetic coding of an arbitrary shaped slip surface, the definition of the optimization fitness function, and the constraint of rational shapes of potential slip surfaces. The feasibility, efficiency, and robustness of the genetic algorithm optimization method were finally demonstrated with stability analysis of a classic slope case.