基于随机地震动模型的双洞平行地铁隧道净距影响研究

Research on the Influence of the Distance Between Double-hole Parallel Tunnel Based on Stochastic Earthquake Ground Motion Model

为了研究隧道净距对双洞平行地铁隧道抗震性能的影响,以常州地铁1号线为工程背景,建立有限元分析模型,基于随机地震动模型合成随机地震动,对双洞平行隧道进行随机地震动作用下的地震动力反应分析。结果表明,随机地震动作用下,双洞平行隧道之间存在相互作用,相互靠近一侧各点动力响应均比外侧各点强烈;隧道间净距过小会造成衬砌结构明显水平位移偏移,且在隧道内下侧出现应力集中现象。在实际工程运用中,应提前对小净距隧道结构采取预加固等措施,预防地震对隧道造成大面积破坏。

In order to study the influence of the spacing on the seismic performance of the double parallel tunnel, the finite element model is established based on Changzhou Metro Line 1. The dynamic response analysis is carried out by using the ground motion based on stochastic earthquake ground motion model. The results show that the tunnels interact with each oth- er under the stochastic earthquake ground motion and the dynamic response of points inside is stronger than that outside. The small distance between the tunnels will cause obvious horizontal displacement of lining structure and the stress concentration will appear in the lower inner side of the tunnel. In practical engineering, some measures should be taken in advance to re- inforce the tunnel structure to protect it from the large damage.