多点输入地震作用下长大隧道的动力灾变研究

With the development of economic and urbanization, many cross-river and cross-ocean tunnels have been planed or built. The span of these tunnels' is usually several kilometers. For these long span tunnels, the input seismic loads have the feature of spatially varying, therefore it is necessary to do the nonlinear seismic analysis of these tunnels under the action of spatial varying ground motions. This research proposes the methods to simulate the spectral compatible uniform ground motions and spatially varying ground motions, gives the method to do the seismic response analysis of tunnels under the action of spatial varying ground motions. Then, the seismic response of tunnels under the action of spatially varying ground motions is really achieved, and the seismic response characters of these tunnels are revealed. Hence, the earthquake seismic resistant methods are proposed. The results of this research can be applied to Gongbei Tunnel of Hong Kong-Zhuhai-Macao Bridge. The results can enhance the tunnel seismic response analysis and seismic resistant theory, and can be valuable to the seismic resistance of Gongbei Tunnel of Hong Kong-Zhuhai-Macao Bridge, and can give useful suggestions to seismic resistance of other long tunnels.

随着社会经济的发展和城市化进程的加快，我国建成、在建及规划了大量的过江、过海隧道，这些隧道的跨度常常达到几千米。长大隧道的地震荷载具有多点输入的特点，需要采用非线性多点地震耦合反应进行长大隧道的抗震分析。本项目研究拟提出了反应谱相拟合的一致输入和多点输入地震动的合成方法，建立隧道多点输入地震反应分析方法，实现真正意义上的多点输入地震作用下长大隧道动力灾变数值模拟，揭示长大隧道地震灾变特性，进而有针对性地提出长大隧道地震灾变控制方法。以港珠澳大桥珠海连接线拱北隧道作为依托工程，进行工程应用研究。研究成果将丰富隧道地震动灾变分析与控制理论，对港珠澳大桥珠海连接线拱北隧道工程抗震有重要的应用价值，对其它长大隧道抗震也有较好的借鉴意义。

随着社会经济的发展和城市化进程的加快，我国建成、在建及规划了大量的过江、过海隧道，这些隧道的跨度常常达到几千米。对长大隧道地震动力响应分析时，需进行非一致地震动进行输入。项目研究中从非一致地震动模拟这一基础工作入手，提出了反应谱相拟合的一致输入和多点输入地震动的模拟方法。基于动力有限元数值模拟，开展了一致输入地震动作用下和非一致输入地震作用下长大隧道动力响应分析研究。研究指出：在非一致地震作用下，隧道的应力和位移响应会显著高于一致地震作用下的响应，即考虑地震动的非一致性会似的动力响应分析结果更偏于安全。研究成果丰富了隧道地震动灾变分析与控制理论，对长大隧道抗震设计也有较好的借鉴意义。