Deformation mechanism and limit support pressure of cutting steel plate during connection between pipes in large spacing using pipe curtain structure method  

作　　者：Xiang Liu Rui Zhang Jun Huang Guang Zhao Qian Fang Annan Jiang 

机构地区：[1]Liaoning Key Laboratory of Marine Environmental Bridge and Tunnel Engineering,Dalian Maritime University,Dalian 116026,China [2]JSTI Group,Nanjing 210017,China [3]Key Laboratory for Urban Underground Engineering of Ministry of Education,Beijing Jiaotong University,Beijing 100044,China

出　　处：《Underground Space》2024年第5期83-96,共14页地下空间（英文）

基　　金：financial support by the National Natural Science Foundation of China(Grant No.52108363);the Postdoctoral Research Foundation of China(Grant Nos.2021M700654 and 2023T160074);the Key Project of High-speed Rail Joint Fund of National Natural Science Foundation of China(Grant No.U1934210);the Liaoning Revitalization Talents Program(Grant No.XLYC1905015);the Key Project of Liaoning Education Department,China(Grant No.LJKZZ20220003).

摘　　要：The pipe curtain structure method(PSM)is a novel construction method to control ground deformation strictly.Compared with the traditional pipe-roofing and pipe jacking method,the connection between pipes in large spacings using PSM is widely acknowledged as a unique construction procedure.Further study on this connection procedure is needed to resolve similar cases in that the pipes are inevitably constructed on both sides of existing piles.Cutting the steel plate during the connection procedure is the first step,which is crucial to control the safety and stability of the surrounding environment and existing structures.The deformation mechanism and limit support pressure of the cutting steel plate during the connection between pipes in large spacings are studied in this paper,relying on the undercrossing Yifeng gate tower project of Jianning West Road River Crossing Channel in Nanjing,China.A modified 3D wedge-prism failure model is proposed using the 3D discrete element method.Combined with Terzaghi loose earth pressure theory and the limit equilibrium theory,the analytical solutions for the limit support pressure of the excavation face of the cutting steel plate are derived.The modified 3D wedge-prism failure model and corresponding analytical solutions are categorised into two cases:(a)unilateral cutting scheme,and(b)bilateral cutting scheme.The analytical solutions for the two cases are verified from the numerical simulation and in-situ data and compared with the previous solutions.The comparative analysis between the unilateral and bilateral cutting schemes indicates that the bilateral cutting scheme can be adopted as a priority.The bilateral cutting scheme saves more time and induces less ground deformation than the unilateral one due to the resistance generated from the superimposed wedge.In addition,the parametric sensitivity analysis is carried out using an orthogonal experimental design.The main influencing factors arranged from high to low are the pipe spacing,the cutting size,and the pipe burial depth

关 键 词：Pipe curtain structure method Wedge-prism failure model Limit support pressure Discrete element method Connection between pipes 

分 类 号：U45[建筑科学—桥梁与隧道工程]