考虑参数模糊随机性的风化板岩边坡广义可靠性分析研究  

Generalized Reliability Analysis of Weathered Slate Slope Considering Fuzzy Randomness of Parameters

作　　者：刘文劼 巢万里 郭一鹏 LIU Wenjie;CHAO Wanli;GUO Yipeng(Hunan Communication Research Institute Co.Ltd.,Changsha 410015;School of Civil Engineering,Changsha University of Science and Technology,Changsha 410076)

机构地区：[1]湖南省交通科学研究院有限公司,长沙410015 [2]长沙理工大学土木工程学院,长沙410076

出　　处：《土工基础》2024年第4期691-696,共6页Soil Engineering and Foundation

基　　金：国家自然科学基金青年基金(52208352);湖南省交通科技项目(202238)。

摘　　要：为研究岩土参数随机性和模糊性对边坡稳定性的影响,依托湖南某高速公路板岩边坡,开展了利用隶属度函数和Rosenblueth法的边坡广义可靠性分析,将其与传统定值安全系数法进行了对比,并研究了隶属度函数形式、截集个数对边坡广义可靠性的影响规律,给出了合理的分析计算方案建议。研究表明:不同截集水平下的安全系数均值无法反映岩土参数模糊性,而可靠性指标与参数模糊性具有较好的关联,随着模糊截集水平的增大,可靠性指标提高,得出该边坡失效概率等于0.889%,处于稳定状态,同定值安全系数法相比与实际情况更加吻合;参数隶属度函数的形式与截集个数对广义可靠性指标影响较大,为了在较少的计算量下得到较高的计算精度,建议优先选择梯形或三角形的隶属度函数,截集个数选择9个;广义可靠性分析考虑了抗剪强度参数的模糊随机性,回避了定值安全系数法参数取值的精确性难题,其稳定性判断的思想更加科学,可供类似边坡分析参考借鉴。To study the influence of the randomness and fuzziness of geotechnical parameters on the slope stability,this paper presents a case history of a slate slope of an expressway in Hunan Province.The generalized reliability analysis is performed by using the membership function and the Rosenblueth method.The method is compared with the traditional method with a fixed safety factor.The membership function and cut-set numbers influence on reliability are studied.Suggestions for the reasonable analysis are proposed.The results show that the mean value of safety factors at different cut-set levels cannot reflect the fuzziness of geotechnical parameters,while the reliability index has a good correlation with the fuzziness of parameters.With the increase of the fuzzy cut-set level,the reliability index increases.For this slope,the failure probability obtained by the fuzzy reliability method is 0.889%<5%,which means a stable state and is more consistent with the actual situation compared with the fixed safety factor method.The parameter membership function form and the cut-set number have a great influence on the generalized reliability index of slope.When using fuzzy point estimation method,the trapezoidal or triangular membership distribution should be selected first.The number of cut-set is suggested to be nine.The generalized reliability analysis of the slope considers the fuzzy randomness of the shear strength parameters,avoiding the problem of the parameter accuracy of the fixed safety factor method.Therefore,the thinking of slope stability judgment is more scientific.The study results provide a reasonable reference for the analysis of similar slope projects.

关 键 词：边坡 板岩 模糊随机性 广义可靠性 隶属度函数 截集 

分 类 号：TU457[建筑科学—岩土工程]