隧道纵向地震反应分析方法及抗震性能研究

Tunnel engineering is an important part of lifeline engineering, more and more attentions are paid to its seismic problems. Research of the program focuses on tunnel structure, and further study of seismic problems of tunnels is conducted by means of theoretical analysis and numerical simulation. Employing the calculation method of free-field motion under oblique wave, A FORTAN program is compiled to simulate the asynchronous seismic input. The dynamic analysis model of tunnel-foundation system under asynchronous wave is established, and the dynamic analysis method is proposed. A systematic comparative study on practical seismic analysis method for longitudinal seismic response of tunnels is conducted. Some improvements of the classical response deformation method are made, and the integral response deformation method for longitudinal seismic response of tunnels is proposed. The research builds discontinuity analytical model which can simulate the connection of segment and tunnel, and numerical analysis is carried out using the model. The dynamics reaction rules and failure mechanism are studied, and the qualified performance indexes of tunnels are put forward. The program has important significance of exploring reasonable and reliable longitudinal seismic analysis and design methods of tunnel structure.

隧道工程是重要的生命线工程，其抗震问题日益受到重视。本项目以隧道结构为研究重点，采用理论分析和数值模拟手段对隧道抗震问题进行深入研究。基于地震波斜入射时自由波场计算方法，编制非一致地震动输入辅助程序, 建立可考虑非一致地震动作用的隧道-地基系统动力相互作用分析模型，并以此发展非一致地震动作用下的隧道-地基动力有限元分析方法；对现有隧道纵向抗震实用分析方法进行综合比较，并对传统反应位移法进行改进，提出一种适用于隧道纵向抗震分析的整体式反应位移法；建立一种合理的模拟盾构隧道中管片与接头不连续性的分析模型，开展系统的数值模拟分析，研究盾构隧道动力反应影响参数、动力反应规律和破坏机理，并初步提出适用于隧道结构的抗震性能量化指标体系。项目工作对发展合理而可靠的隧道纵向抗震分析方法及完善隧道结构抗震设计理论均有重要意义。

隧道结构作为生命线工程的重要组成部分，一旦遭遇地震灾害，其破坏隐蔽、修复困难的弊端将会造成严重的经济损失和人员伤亡。本项目以隧道结构为研究重点，采用理论分析和数值模拟手段对隧道等长线型地下结构纵向抗震问题进行了深入研究。基于地震波斜入射时自由波场一维化时域算法，编制了非一致地震动输入辅助程序，发展了非一致地震动输入下隧道-地基系统动力时程分析方法；基于有限元离散化模型，完成了地下结构横向抗震分析整体式反应位移法的理论推导；在此基础上，提出了适用于隧道等长线型地下结构纵向地震反应分析的整体式反应位移法，给出了根据自由场地震反应确定隧道纵向最不利变形和内力发生时刻的方法；并将此实用分析方法应用于大空间隧道结构以及埋置于非均匀场地中隧道结构的纵向抗震问题。项目工作对于发展隧道结构纵向地震反应分析方法，提高隧道结构地震安全性能、完善我国隧道结构抗震设计理论均具有重要意义。