基于Midas GTS有限元软件的下穿既有轨道交通结构安全保护研究  

Safety Protection of Under-passing Existing Rail Transit Structures Based on Midas GTS Finite Element Software

作　　者：顾章川 GU Zhangchuan(China Design Group Co.,Ltd.,210014,Nanjing,China)

机构地区：[1]华设设计集团股份有限公司,南京210014

出　　处：《城市轨道交通研究》2025年第3期181-185,191,共6页Urban Mass Transit

基　　金：华设设计集团股份有限公司科研项目(KY2021026)。

摘　　要：[目的]随着城市轨道交通网络的迅速扩张,多线路交织穿越已成为城市建设的普遍现象,特别是新建隧道以矿山法施工方式下穿既有轨道交通结构的情况日益增多,故有必要对下穿既有轨道交通结构安全保护进行深入研究。[方法]以某市轨道交通8号线矿山法隧道下穿既有轨道交通3号线安全防护项目为依托,运用Midas GTS有限元软件,模拟了不同外部作业工况对上部已建轨道交通结构的影响。通过对各施工工序下既有轨道交通结构变形特征的详细分析,以及数值模拟结果与现场监测数据的对比分析,探讨了施工对既有结构的影响。[结果及结论]数值模拟结果显示:新建轨道交通8号线采用矿山法下穿隧道施工时,引起的既有轨道交通结构变形均在控制指标范围内。主体结构的水平位移最大值为0.54 mm,竖向位移最大隆起量为1.92 mm。而现场实测数据显示,既有轨道交通主体结构的水平位移最大值为0.50 mm,竖向位移最大值为1.60 mm。这表明,在合理选取参数的前提下,数值模拟作为一种安全风险评估手段,其模拟结果与实测值较为吻合。此外,数值模拟还能准确预测结构受影响的最不利位置及程度,对现场施工及监测具有重要的指导作用。[Objective]With the rapid expansion of urban rail transit networks,the intersection of multiple lines has become a common phenomenon in urban construction.In particular,the increasing cases of newly constructed tunnels using the mining method under-passing existing rail transit structures necessitate in-depth research on the safety protection of these structures.[Method]Based on the safety protection project of a city′s Rail Transit Line 8 mining method tunnel under-passing existing Rail Transit Line 3,Midas GTS finite element software is used to simulate the impact of different external working conditions on the upper part existing rail transit structure.Through a detailed analysis of the deformation characteristics of the existing rail transit structure under various construction procedures,as well as a comparative analysis of numerical simulation results and the on-site monitoring data,the construction impact on above-mentioned existing structures is explored.[Result&Conclusion]Numerical simulation results show that when the new Metro Line 8 using mining method for the under-passing tunnel construction,the deformations of the existing rail transit structure remain within the control indicators.The maximum horizontal displacement of the main structure is 0.54 mm,and the maximum upward deflection of vertical displacement is 1.92 mm.On-site measured data indicate that the maximum horizontal displacement of the existing rail transit main structure is 0.50 mm,and the maximum vertical displacement is 1.60 mm.This shows that under reasonable parameter selection,numerical simulation,as a safety risk assessment tool,provides simulation results in good agreement with actual measurements.Additionally,numerical simulation can accurately predict the most adversely affected positions and the extent of structural impact,providing significant guidance for on-site construction and monitoring.

关 键 词：隧道施工 下穿轨道 安全保护 变形监测 

分 类 号：TP3[自动化与计算机技术—计算机科学与技术] TV554.4[水利工程—水利水电工程]