Deformation analysis of surface and retaining wall induced by braced excavation based on random field theory
YI Shun1，2，3，4，LIN Weining5，CHEN Jian1，2，3，4，HUANG Juehao1，2，3，4，LI Jianbin6，WU Jiaming7，8
(1. State Key Laboratory of Geomechanics and Geotechnical Engineering，Institute of Rock and Soil Mechanics，Chinese Academy of Sciences，Wuhan，Hubei 430071，China；2. University of Chinese Academy of Sciences，Beijing 100049，China；3. Hubei Key Laboratory of Geo-Environmental Engineering，Institute of Rock and Soil Mechanics，Chinese Academy of Sciences，Wuhan，Hubei 430071，China；4. The Soft Soil Research Center in Ningbo University of Technology，State Key Laboratory of Geomechanics and Geotechnical Engineering，Ningbo，Zhejiang 315211，China；5. Jinhua Rail Transit Group Co.，Ltd.，Jinhua，Zhejiang 321000，China；6. School of Civil Engineering，Guangzhou University，Guangzhou，Guangdong 510006，China；7. China Railway Siyuan Survey and Design Group Co.，Ltd.，Wuhan，Hubei 430063，China；8. National and Local Joint Engineering Research Center of Underwater Tunnelling Technology，Wuhan，Hubei 430063，China)
Abstract：Based on the small strain model，the random field theory is combined with the finite analysis method to study the influence of the spatial variability of stiffness parameters on the surface and retaining wall deformation induced by braced excavation. A series of isotropy random field models of clay stiffness are generated by Covariance Matrix Decomposition method. With Monte-Carlo framework，the paper analyzes the influence of coefficients of variation and scales of fluctuation on the surface settlement and retaining wall deflection. The results show that the spatial variability of stiffness parameters in clay has an important influence on surface settlement and retaining wall deflection. The surface settlement and the maximum deformation ratio are the most dispersed when the scales of fluctuation is close to the excavation size while similar conclusion has not been drawn in retaining wall deflection. Compared with the corresponding deterministic results，the mean values of maximum surface settlement and maximum retaining wall deflection show different results in the stochastic analysis because of the dominant effect of low stiffness. With the help of probability statistics method，the paper studies the possibility of surface settlement and retaining wall deflection exceeding the monitoring control values，which can provide a reference for the safety warning for the maximum deformation induced by braced excavation before construction.
易 顺1，2，3，4，林伟宁5，陈 健1，2，3，4，黄珏皓1，2，3，4，李健斌6，吴佳明7，8. 基于随机场理论的基坑开挖地表及围护墙变形分析[J]. 岩石力学与工程学报, 2021, 40(S2): 3389-3398.
YI Shun1，2，3，4，LIN Weining5，CHEN Jian1，2，3，4，HUANG Juehao1，2，3，4，LI Jianbin6，WU Jiaming7，8. Deformation analysis of surface and retaining wall induced by braced excavation based on random field theory. , 2021, 40(S2): 3389-3398.
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2021, Vol. 40 
