改进的TOPSIS(逼近理想解排序方法)在土体刚度参数反分析中的应用

徐世祥1万友生2贺烽2覃君3谢云杰3吴波1,4郑卫强1许杰4

Application of Improved TOPSIS in Back Analysis of Soil Stiffness Parameters

XU Shixiang1WAN Yousheng2HE Feng2QIN Jun3XIE Yunjie3WU Bo1,4ZHENG Weiqiang1XU Jie4
摘要:
[目的]当采用反分析法确定土体参数时,由现场实测得到的理想解一般为中间值,无法使用传统的 TOPSIS(逼近理想解排序法)进行计算。有必要改进传统TOPSIS,并与熵权法、数值分析法和正交试验法相结合,应用于土体刚度参数反分析。[方法]简述了传统TOPSIS的改进,并与熵权法、数值分析和正交试验法相结合,应用于富水砂层刚度参数反分析中。利用正交试验法建立了25个方案数值分析模型,选取最大地面沉降、最大拱顶沉降、最大拱底隆起和最大净空收敛4个指标进行综合决策,确定了适用于富水砂层土体硬化模型刚度参数的比例关系与大小。[结果及结论]改进的TOPSIS能有效地与数值分析和正交试验法相结合进行反分析研究,科学地对正交试验方案进行多指标决策,为复杂岩土工程反分析理论提供了一种新的决策方法。富水砂层土体硬化模型刚度参数之间的比例关系为:固结试验切线模量Eref,oed=Es(0.1~0.2)(0.1~0.2 MPa围压下的压缩模量),三轴固结排水剪切试验割线模量Eref,50=1.4Eref,oed,三轴固结排水卸载再加载试验的卸载再加载模量Eref,ur=2.0Eref,50,刚度应力相关指数为0.6。
Abstracts:
[Objective] When the back analysis method is used to determine soil parameters, the ideal solution obtained from field measurements is generally an intermediate value, which cannot be calculated using the traditional TOPSIS (technique for order preference by similarity to solution). It is necessary to improve the traditional TOPSIS and combine it with the entropy weight method, numerical analysis method and orthogonal test method for back analysis of soil stiffness parameters. [Method] The improved traditional TOPSIS is briefly described and combined with entropy weight method, numerical analysis and orthogonal test method, then applied to the back analysis of stiffness parameters in water-rich sandy stratum. 25 numerical analysis models of the schemes are established with the orthogonal test method. Four indicators including maximum ground settlement, maximum arch crown settlement, maximum arch bottom uplift and maximum clearance convergence are selected for comprehensive decision-making, and the proportional relationship and size of the stiffness parameters of the HS (hardening soil) model suitable for water-rich sandy stratum are determined. [Result & Conclusion] The improved TOPSIS can effectively combine numerical analysis and orthogonal experiment method for back analysis research, and make multi-index decisions on orthogonal experiment schemes scientifically, providing a new decision-making method for the back analysis theory of complex geotechnical engineering. The proportional relations between the stiffness parameters of the HS model in water-rich sand stratum are: tangent modulus of consolidation test Eref,oed=Es(0.1~0.2) (0.1~0.2 MPa compression modulus under ambient pressure), the cut line modulus of three-axis consolidation drainage shear test Eref50=1.4Eref,oed , the unloading and reloading modulus of three-axis consolidation drainage unloading and reloading test Eref,ur=2.0Eref,50 , the stiffness stress correlation index equals 0.6.
论文检索