地下T型交叉管廊的抗震时程分析

Seismic time-history analysis of T-type underground utility tunnels

利用ABAQUS有限元软件,进行地下T型交叉管廊的抗震时程分析。计算模型采用黏弹性边界结合地震动输入等效节点力的方法建立,土体的非线性采用等价线性方法考虑,混凝土材料采用塑性损伤模型模拟。以某拟建的双舱地下综合管廊工程为例,研究了T型交叉管廊在地震波激励下的内力。研究表明,T型交叉管廊交界面的内力最大;相比于非交叉管廊,在T型交叉管廊交界面位置处,T型交叉节点对轴线与振动方向一致的管廊的截面弯矩影响最大,放大了233倍;T型交叉节点对轴线与振动方向垂直的管廊的轴力影响最大,放大了17倍。研究对于T型交叉管廊的抗震设计具有一定参考价值。

ABAQUS finite element software is used to conduct seismic time-history analysis of the T-type underground utility tunnels.The calculation model is established by using the viscoelastic boundary method combined with the ground motion input equivalent nodal force method,the soil nonlinearity is considered by the equivalent linear method,and the concrete nonlinearity is considered by plastic damage model.Taking T-type utility tunnels of two cabins to be built as an example,the internal forces under seismic wave are calculated.It is shown that,the maximum internal forces are found at the T-type joint interface;compared with the non-cross utility tunnels,the T-type joint has the most significant influence on the section bending moment of the utility tunnel whose axis is along with the vibration direction,with a magnification of 233 times,and the T-type joint has the most significant influence on the axial force of the utility tunnel whose axis is perpendicular to the vibration direction,with a magnification of 17 times.This study has certain reference value for the seismic design of T-type underground utility tunnels.