基于Monte-Carlo法的软土路基工后沉降可靠性分析

基于Monte-Carlo方法,对某高速公路软土路基段工后沉降进行可靠性分析,并推导出了软土路基工后沉降极限状态方程,编写了简单计算程序。应用结果表明,汉洪高速公路软基工后沉降大于30cm的概率非常小,大于20cm的概率较小,而大于10cm的概率相对较大;当工后沉降容许值较大时,基于定值方法得出的估算路基工后沉降的规律与基于可靠度方法得出的规律是一致的;而当工后沉降容许值较小时,可靠度方法能更好地考虑参数变化影响,优于定值方法。

Reliability Analysis of Soft Ground Post-construction Settlements Based on Monte-Carlo Method

On the basis of the Monte-Carlo method, this article presents a reliability analysis of post-construction settlements for soft ground of expressway. A limit state function for post-construction settlements is deduced using Monte-Carlo method; meanwhile a simple calculating program is presented. The project application result indicates that the probability of post-construction settlement greater than 30cm is extremely small, also greater than 20cm is small. But the probability of greater than 10cm is relatively high. If the allowed settlement of post-construction is relatively high, the estimated post-construction settlement law by definite value method is the same to that by Monte-Carlo method. However, if the allowed settlement of post-construction is small, the reliability method can reflect the influence of parameters variation to the settlements. Therefore, the reliability method is prior to the definite value method.