盾构下穿地铁区间隧道衬砌受力特征分析

The Stress-Strain Characteristics the Lining of a Shielded Metro Tunnel underneath the Existing Tunnels

考虑时空效应的盾构下穿既有地铁隧道结构受力特征计算,对盾构工程风险控制研究有着重要意义。以南京地铁新建三号线区间盾构下穿既有一号线矿山法区间隧道为例,利用有限差分软件,按施工过程对既有一号线隧道衬砌结构的受力特征进行计算分析。结果表明:在采取有针对性的工程措施后,盾构下穿既有矿山法隧道施工方案是可行的。

The prediction of the loads and their time effects on the lining system of a shielded metro tunnel crossing the existing tunnels is an important factor in the risk control of the shield construction. This paper records a case history of the proposed No. 3 shielded regional metro line underneath the existing No. l metro line in Nanjing City. The finite difference method was used in the analysis the impact of the No. 3 line construction on the lining system of the existing No. 1 line. The results indicated that the current shield construction technology was appropriate and would not adversely affect the existing tunnel lining. Key words Shielding Crossing, Mining Method Tunnel, Stress-Strain Characteristics, Time Effect, Numerical Simulation.