考虑海水-海床耦合效应的海底隧道地震响应研究  

SEISMIC RESPONSE OF SUBSEA TUNNELS CONSIDERING SEAWATER SEABED COUPLING EFFECT

作　　者：陈炜昀[1,2] 吕振宇 徐令宇 阮滨[3] 马建军 陈国兴 CHEN Weiyun;LU Zhenyu;XU Lingyu;RUAN Bin;MA Jianjun;CHEN Guoxing(Institute of Geotechnical Engineering,Nanjing Tech University,Nanjing 210009,China;School of Civil Engineering,Sun Yat-Sen University,Guangzhou 510275,China;School of Civil and Hydraulic Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]南京工业大学,岩土工程研究所,南京210009 [2]中山大学,土木工程学院,广州510275 [3]华中科技大学,土木与水利工程学院,武汉430074

出　　处：《工程地质学报》2021年第6期1878-1886,共9页Journal of Engineering Geology

基　　金：国家自然科学基金(资助号:41877243);江苏省自然科学基金(资助号:BK20201363).

摘　　要：在近海海域修建海底隧道必须考虑地震灾害的潜在威胁,进行海底隧道地震响应研究时考虑海水动水压力的影响将更贴合实际情况。为研究考虑海水-海床耦合效应的海底隧道地震响应规律,本文基于某海峡海底盾构隧道工程,考虑了海床土体和隧道混凝土的动力非线性特性以及海水与海床之间的耦合效应,建立了海水-海床-隧道动力相互作用的有限元模型,研究了在不同地震动输入、不同地震激励方向、不同上覆水深条件下海底隧道的地震响应规律。结果表明:使用ABAQUS中的声学模块能够有效地实现流-固耦合作用的模拟;在水平地震作用下,隧道在左右拱肩及拱脚位置应力集中显著;地震作用时水域最大动水压力出现在隧道正上方左右两侧海床表面处;当处于双向地震激励时,海床表面动水压力显著增大,隧道各点处的应力峰值也随之显著增大;相较于高频丰富的地震动,低频丰富的地震动输入对海底隧道的影响更大;海底隧道地震损伤随着水深增加逐渐减小。研究结果有助于更好地掌握实际海底隧道地震响应规律。The potential threat of earthquake disaster should be considered in the construction of subsea tunnel in offshore areas.Considering the influence of seawater hydrodynamic pressure can be more in line with the actual situation when analyzing the seismic response of subsea tunnel.A seismic analysis model of water-seabed-tunnel is established,which takes into account the nonlinearity of soil and the fluid-structure interaction between seawater and seabed.The seismic response of undersea tunnel under different seismic excitations and water depths is studied.The results show that the acoustic module can simulate the fluid-structure interaction well.Under the action of horizontal earthquake,the stress of tunnel is mainly concentrated at the arch shoulder and arch foot.The maximum hydrodynamic pressure in the calculated area under earthquake action occurs on the left and right sides of the seabed above the tunnel.Under bidirectional seismic excitation,the hydrodynamic pressure on the seabed surface increases significantly,and the stress peak at each point of the tunnel also increases significantly.The seismic response of subsea tunnel under the earthquake with rich low frequency component is much stronger than that with rich high frequency component.Seismic damage of subsea tunnel decreases with the increasing water depth.The results are of some reference value for understanding the actual seismic response law of the undersea tunnel.

关 键 词：海底隧道 海水-海床耦合 地震响应 动水压力 地震损伤 

分 类 号：P751[交通运输工程—港口、海岸及近海工程]