城市地下管廊结构地震动力响应分析

Seismic Dynamic Response Analysis of Urban Underground Utility Tunnel Structure

地震安全问题是城市地下管廊设计中不得不考虑的部分.先使用反应位移法计算地震时管廊结构的内力,得出管廊薄弱部位.接着使用动力时程方法分析管廊的地震响应,建立土体与结构数值模型,在模型底部输入水平地震作用.采用土-结构界面接触单元,重点考虑土与结构之间的相互作用,得出结构与土之间的分离与滑移情况以及管廊在水平地震作用下的位移变形和应力分布.结果发现:地下管廊标准段结构在水平地震作用下发生明显的侧向位移,容易发生弯剪破坏,而水平方向未发生明显位移;管廊结构地震破坏时的薄弱环节在顶板、底板与侧墙的连接部位以及中隔墙的墙端,在抗震设计中需采取加固措施.

Seismic safety issues must be considered in the design of urban underground utility tunnel. Firstly, the reaction displacement method was used to calculate the internal force of the utility tunnel structure during the seismic, and the weak part of the utility tunnel was obtained. Then the dynamic time history method was used to analyze the seismic response of the utility tunnel, and the numerical model of the soil, structure was established, and the horizontal seismic action was input at the bottom of the model. The soil-structure interface contact unit was used, and the interaction between soil and structure was considered, and the separation and slip between the structure and the soil,the displacement deformation and stress distribution of the utility tunnel under horizontal seismic were obtained. The results show that the standard section structure of the underground utility tunnel has obvious lateral displacement under the action of horizontal seismic action, which is prone to bending and shear failure, but no obvious displacement in the horizontal direction. The weak link in the seismic damage of the utility tunnel structure is on the roof, the bottle plate and the side wall, as well as the wall end of the partition wall, and reinforcement measures are required in the seismic design.