边坡可靠性评价的最优化Monte Carlo方法及应用

岩土力学参数具有一定的随机性和复杂性,在边坡可靠度指标计算过程中,功能函数常常为隐式表达形式,这对可靠性指标的求解带来一定的难度.借用响应面思想,利用试验结果拟合近似稳定系数计算方程从而替代隐式方程,并建立近似极限状态方程,则可很好地解决这一问题.介绍了最优化可靠度计算的基本思想,以广东高速公路仙水河大桥3号桥墩边坡为例,通过构造响应面函数,编制计算边坡可靠度的最优化方法及基于最优化原理的蒙特卡罗法Matlab程序,对该边坡的可靠性进行了评价.结果表明,基于响应面法的可靠性最优化方法用于边坡可靠度设计具有足够的精度,该方法求解简便,克服了传统方法受极限方法及随机变量概型限制的缺陷,求解精度高,为边坡可靠性评价提供了一条新的途径.

Optimization Monte Carlo Method of Slope Reliability Evaluation and Its Application

Rock mechanics parameters have certain randomicity and complexity,in the slope reliability index calculation process,the function is often implicit expression,so it gets the difficulty for solution of reliability index.Using the response surface thoughts and test results,the fitting calculation equation and approximate stability coefficient equations and alternative implicit approximate limit state equation established can solve this problem.The basic ideas of optimum reliability calculation are introduced,as Guangdong expressway Xianshuihe river bridge No.3 pier slope for an example,through the structural response surface function,the optimization method calculation of slope reliability and Monte Carlo method Matlab program based on the optimization principle is carried out,and the reliability of slope is evaluated.The results show that the response surface method based on reliability optimization methods are used to slope reliability design,the method has simple solution,enough precision,and overcome the shortcomings of the traditional method with the restricted of limited method and random valuables probabilistic models,so it provides a new way for the reliability evaluation of slope.