基于支持向量机的土体压缩性变形参数多目标反分析方法  

Multi-objective Back Analysis Method of Soil Compressibility and Deformation Parameters Based on Support Vector Machine

作　　者：李梅[1] 冯亚腾 郑筱彦 王斌 LI Mei;FENG Ya-teng;ZHENG Xiao-yan;WANG Bin(School of Resources and Environmental Engineering,Wuhan University of Technology,Wuhan 430070,China;China Railway Construction Group Co Ltd,Beijing 100040,China;Institue of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China)

机构地区：[1]武汉理工大学资源与环境工程学院,武汉430070 [2]中铁建设集团有限公司,北京100040 [3]中国科学院武汉岩土力学研究所,武汉430071

出　　处：《武汉理工大学学报》2021年第1期85-91,共7页Journal of Wuhan University of Technology

基　　金：国家自然科学基金(51104111);山东省重大科技创新工程(2019JZZY020314)。

摘　　要：压缩指数、回弹指数以及次固结系数是表征土体压缩性的重要变形参数,通常被用来计算工程土体沉降,其值获取目前多采用室内固结蠕变试验,但试验结果受多方面因素影响,耗时长且精确度较低。基于此,提出一种基于支持向量机和非支配排序遗传算法(NSGA-Ⅱ)的多目标反分析方法来获取土体压缩性变形参数,首先通过开展原状土室内标准固结试验获取变形参数的取值范围,并利用支持向量机建立变形参数与水平及竖向位移之间的非线性映射关系,最后使用NSGA-Ⅱ算法求解多目标函数,得到土体变形参数的最优解,比较最优土体变形参数的数值模拟位移与现场监测位移,结果吻合,说明该方法可行。Compression index,rebound index,and secondary consolidation coefficient are important deformation parameters that characterize soil compressibility.They are usually used to calculate the settlement of engineering soils.At present,its value is mostly obtained by indoor consolidation creep test,but the test result is affected by many factors,which takes a long time and has low accuracy.Based on this,the paper proposes a multi-objective back analysis method based on support vector machine and non-dominated sorting genetic algorithm(NSGA-Ⅱ)to obtain soil compressive deformation parameters.Firstly,the range of deformation parameters was obtained by carrying out the standard consolidation tests of undisturbed soil,and the nonlinear mapping relationship between deformation parameters and horizontal and vertical displacement was established by support vector machine.Finally,NSGA-Ⅱ algorithm was used to solve the multi-objective function,and the optimal solution of soil deformation parameters was obtained.Comparing the numerical simulation displacement of the optimal soil deformation parameters with the on-site monitoring displacement,the results are consistent,indicating that the method is feasible.

关 键 词：土体压缩性变形参数 反分析 多目标 固结试验 支持向量机 

分 类 号：TU43[建筑科学—岩土工程]