小净距隧道施工顺序FLAC^(3D)模拟分析

Numerical Simulation Analyses on the Construction Sequence of Twin-tunnel with Short Separation by FLAC^(3D)

以云南某地双线隧道工程为背景,采用FLAC3D数值模拟研究方法,对小净距隧道采用"同向滞后开挖"和"对向开挖"2种施工顺序下施工过程中的力学行为进行了对比分析,揭示出不同施工顺序下的地层剪应变增量、变形位移、应力及塑性区分布等相关方面的研究成果,得出"对向开挖"的施工方案优于"同向滞后开挖"方案的结论。同时也表明FLAC3D用于隧道围岩变形分析是可行的。

In accordance with one twin-tunnel with short separation in Yunnan province, a comparative study was carried out by numerical simulation program FLACw on the behavior of the construction process of two closely-spaced parallel tunnels, considering two options of construction, namely asynchronous excavation in the same direction and excavation in op- posite direction. Results of the numerical analyses indicate, with different construction sequence of twin-tunnel, many rea- sonable conclusions on relevant research, such as shear strain increment, the maximum displacement, the maximum prin- cipal stresses, the plastic zones and so on, are gained. At the same time, the article revealed the result of the excavation in opposite directions is much better than the other option. Finally, the article indicates that FLAC^3D is very capable of solving the deformation analysis of the tunnel surrounding rock.