Inverse Analysis and Optimization of SMW Pile Parameters Based on Orthogonal Numerical Test
(1. School of Civil and Architectural Engineering, Nanchang Institute of Engineering, Nanchang 330029; 2. Jiangxi Tianchi HighSpeed Technology Development Co., Ltd., Nanchang 330000; 3. Jiangxi Academy of Transportation Sciences, Nanchang 330200;4. School of Architectural Engineering, Zhejiang University, Hangzhou 310058)
Abstract:
The finite element analysis is used to establish a model to study the influence of foundation pit excava? tion on the horizontal deformation of adjacent tunnels. The influence of five factors on the deformation of adjacent tunnels is analyzed, including the insertion ratio of the SMW pile, the spacing of inserted steel, the type of inserted steel, the diameter of the cement-soil pile, and the pre-axial force of steel support. The orthogonal test visualizes the influence degree, and the design parameters of the SMW pile are optimized by the regression method. The results show that the change in the type of SMW retaining structure has little effect on the deformation of the adjacent tunnel. When the pile insertion ratio exceeds 2.0, the increase of the insertion depth of the retaining pile has little effect on the horizontal displacement of the tunnel. The diameter of the cement-soil pile has the most significant influence on the horizontal deformation of the adjacent tunnel, followed by the pre-axial force of the steel support. The influence of the spacing of the inserted steel in a pile should also be paid attention to. When the pile insertion ratio is between 1.0 and 2.5, it can be regarded as a non-major factor affecting the horizontal deformation of the adjacent tunnel;based on the orthogonal test, it is feasible to use the regression method to fit the regression equation to calculate the optimal parameter combination, and the obtained parameter combination is superior to the orthogonal test
JU Haiyan1 LIU Xingxing1 ZHOU Yang2 WAN Ling3,
4 LIU Yan1
.Inverse Analysis and Optimization of SMW Pile Parameters Based on Orthogonal Numerical Test[J] MODERN TUNNELLING TECHNOLOGY, 2022,V59(5): 136-143