基于直接积分法的水闸稳定可靠度分析

随着计算机的发展,在计算非线性大变异的极限状态方程和懈决多模态相关问题的可靠度时,直接积分法具有很高的精度.依据直接积分的基本原理,通过理论分析解决了直接积分法的几个关键问题：积分区域的规则化处理,联合概率密度函数构成和多维数值积分计算;编制了能应用于可靠度计算的计算程序,并针对水闸抗滑稳定安全系数公式非线性的特点,借助随机参数的统计分析,计算出已建水闸稳定的可靠度指标和失效概率.与精确的Monte-carlo数值模拟法相比,两者非常接近,从而对水闸的稳定性和安全可靠性作出了评价.由计算可知,水闸稳定的可靠度指标β值受上游水位、摩擦系数f的影响更敏感些.

Analysis of stable reliability for sluice based on direct numerical integration

With the development of computer technology,the direct numerical integration is more accurate in working out the reliability degree of nonlinear and big mutation rate limit state equation and the multimodel-correlation problem.Based on the method of direct numerical integration,this paper investigates the several key problems in calculating reliability with direct numerical integration and completes a direct numerical integration program.Using the method,the failure probability and stable reliability index stable for sluice are calculated according to the data which can be gained from the values of coefficients of vatiation from published sources.The failure probability and stable reliability index are similar as the outcome by the method of Monte-carlo.So both the reliability degree for sluice and its safety degree can be estimated a little more deeply.As shown from the above outcome,the main influencing factors to stability are the upstream water levels and coefficient of internal friction of foundation.