A method which adopts the combination of least squares support vector machine（LS-SVM） and Monte Carlo（MC） simulation is used to calculate the foundation settlement reliability.When using LS-SVM,choosing the traini...A method which adopts the combination of least squares support vector machine（LS-SVM） and Monte Carlo（MC） simulation is used to calculate the foundation settlement reliability.When using LS-SVM,choosing the training dataset and the values for LS-SVM parameters is the key.In a representative sense,the orthogonal experimental design with four factors and five levels is used to choose the inputs of the training dataset,and the outputs are calculated by using fast Lagrangian analysis continua（FLAC）.The decimal ant colony algorithm（DACA） is also used to determine the parameters.Calculation results show that the values of the two parameters,and δ2 have great effect on the performance of LS-SVM.After the training of LS-SVM,the inputs are sampled according to the probabilistic distribution,and the outputs are predicted with the trained LS-SVM,thus the reliability analysis can be performed by the MC method.A program compiled by Matlab is employed to calculate its reliability.Results show that the method of combining LS-SVM and MC simulation is applicable to the reliability analysis of soft foundation settlement.展开更多
深基坑开挖对周边建筑物沉降影响显著,合理的数值模拟方法可为工程设计提供科学依据。论文基于三维有限元方法(Finite Element Method,FEM),建立了包含基坑、支护体系及周边建筑物的数值模型,模拟不同开挖工况及关键因素对沉降的影响。...深基坑开挖对周边建筑物沉降影响显著,合理的数值模拟方法可为工程设计提供科学依据。论文基于三维有限元方法(Finite Element Method,FEM),建立了包含基坑、支护体系及周边建筑物的数值模型,模拟不同开挖工况及关键因素对沉降的影响。研究表明,基坑开挖深度、支护刚度、土层特性及基础形式对建筑物沉降影响显著。浅基础建筑物受基坑开挖影响较大,最大沉降可达30 mm,而桩基础建筑物沉降较小但可能发生桩身侧移。填土地层的沉降量最大,砂土地层表现出显著的差异沉降,而黏土层沉降较均匀但持续时间较长。支护刚度的增加能有效减少地表沉降,但控制效果存在递减趋势。展开更多
文摘A method which adopts the combination of least squares support vector machine（LS-SVM） and Monte Carlo（MC） simulation is used to calculate the foundation settlement reliability.When using LS-SVM,choosing the training dataset and the values for LS-SVM parameters is the key.In a representative sense,the orthogonal experimental design with four factors and five levels is used to choose the inputs of the training dataset,and the outputs are calculated by using fast Lagrangian analysis continua（FLAC）.The decimal ant colony algorithm（DACA） is also used to determine the parameters.Calculation results show that the values of the two parameters,and δ2 have great effect on the performance of LS-SVM.After the training of LS-SVM,the inputs are sampled according to the probabilistic distribution,and the outputs are predicted with the trained LS-SVM,thus the reliability analysis can be performed by the MC method.A program compiled by Matlab is employed to calculate its reliability.Results show that the method of combining LS-SVM and MC simulation is applicable to the reliability analysis of soft foundation settlement.
文摘深基坑开挖对周边建筑物沉降影响显著,合理的数值模拟方法可为工程设计提供科学依据。论文基于三维有限元方法(Finite Element Method,FEM),建立了包含基坑、支护体系及周边建筑物的数值模型,模拟不同开挖工况及关键因素对沉降的影响。研究表明,基坑开挖深度、支护刚度、土层特性及基础形式对建筑物沉降影响显著。浅基础建筑物受基坑开挖影响较大,最大沉降可达30 mm,而桩基础建筑物沉降较小但可能发生桩身侧移。填土地层的沉降量最大,砂土地层表现出显著的差异沉降,而黏土层沉降较均匀但持续时间较长。支护刚度的增加能有效减少地表沉降,但控制效果存在递减趋势。
