基于SPH-FEM数值模拟方法预测水平MJS成桩半径  

Prediction of Horizontal MJS Pile Formation Radius Based on SPH-FEM Numerical Simulation Method

作　　者：程传过 汪庆 CHENG Chuanguo;WANG Qing(China Railway 16th Bureau Group Bejing Rail Transit Engineering Construction Co.Ltd.,Beijing 100018,China;Soochow University,Suzhou Jiangsu 215006,China)

机构地区：[1]中铁十六局集团北京轨道交通工程建设有限公司,北京100018 [2]苏州大学,江苏苏州215006

出　　处：《铁道建筑技术》2025年第3期79-82,149,共5页Railway Construction Technology

基　　金：中铁十六局集团有限公司科技研究开发计划项目(K2020-18C)。

摘　　要：水平MJS(Metro Jet System)是一种常用于地基加固的土体改良技术,其成桩过程中桩体半径受喷射压力、浆液流量、土体特性等多种因素影响。本文采用SPH-FEM(光滑粒子流和有限元耦合)数值模拟方法建立水平MJS射流破土模型,分析不同因素对水平MJS成桩半径的影响,预测实际施工参数下苏州粉砂层中水平MJS的成桩半径。结果表明:水平MJS的成桩半径随喷浆压力和浆流量的增大而增大,当喷浆压力达40 MPa,浆流量为105 L/min时,预估水平MJS成桩半径可达1.05 m,满足成桩半径大于1.0 m的工程要求。数值模拟预测的成桩半径与工程案例的实测值相近证实了模拟结果的可靠性,但实际施工中出现抱钻情况可能导致成桩半径偏小。Horizontal MJS(Metro Jet System)is a soil improvement technique commonly used for foundation reinforcement,where the pile radius during formation is influenced by factors such as injection pressure,slurry flow rate,and soil characteristics.This paper adopts SPH-FEM(smooth particle flow and finite element coupling)numerical simulation method to establish the model of horizontal MJS jet breaking,analyzes the influence of different factors on the pile-forming radius of horizontal MJS,and predicts the pile-forming radius of horizontal MJS in Suzhou silty sand under actual construction parameters.The results indicate that the pile radius increases with higher injection pressure and slurry flow rate.When the injection pressure reaches 40 MPa and the slurry flow rate is 105 L/min,the estimated pile radius of the horizontal MJS can reach 1.05 m,meeting the engineering requirement of a pile radius greater than 1.0 m.The numerical simulation results closely match the measured values from the engineering case,confirming the reliability of the simulation.The occurrence of drill sticking during actual construction may result in a smaller pile radius.

关 键 词：全方位高压喷射注浆(MJS) 成桩质量 成桩半径 数值模拟 

分 类 号：U231.3[交通运输工程—道路与铁道工程]