基于随机响应面法的金鸡岭岩质边坡可靠度分析及抽样方法对比

摘要

The non-invasive analysis model of Jinjiling rock slope stability is established based on the finite element sliding stress method and Hermite stochastic response surface method. The influence of four typical sampling methods like uniform sampling,LHS sampling,improved LHS sampling and stratified sampling on the random response surface's fitting accuracy,slope failure probability and statistical characteristics of safety factor are studied.The results indicate that:(1)Jinjiling rock slope's failure probability is about 18.4%,which is dangerous and needs proper support and reinforcement measures.(2)The random response surfaces constructed by LHS sampling and improved LHS sampling have better fitting accuracy,and the sampling allocation effect is better than that of stratified sampling and uniform design sampling.(3)It is suggested that the sampling allocation of random response surface should be calculated by improved LHS sampling or LHS sampling in the process of non-intrusive random analysis of slope reliability.%结合有限元滑面应力法和Hermite随机响应面法建立了金鸡岭岩质边坡稳定可靠度非侵入式分析模型,在此基础上研究了均匀设计抽样、LHS抽样、改进LHS抽样和分层抽样4种抽样配点方法对随机响应面的拟合精度、边坡失效概率及安全系数统计特征的影响.结果表明:(1)金鸡岭岩质边坡未支护状态下的失效概率约为18.4%,失稳风险较大,需采取支护加固措施;(2)改进LHS抽样和LHS抽样所构造的随机响应面具有较好的拟合精度,抽样配点效果优于分层抽样和均匀设计抽样;(3)建议边坡可靠度非侵入式随机分析采用改进LHS抽样或LHS抽样进行随机响应面的抽样配点计算,并尽可能多地选取样本点以外的验算点对随机响应面拟合精度进行校验.