超大直径过江盾构隧道口字件不同连接型式地震响应特征研究  

Study on Seismic Response Characteristics of Super-large Diameter Shield Tunnel with Different Connection Types of Hinged Joint

作　　者：罗驰恒 LUO Chi-heng(China Railway Siyuan Survey and Design Group Co.,Ltd.,Wuhan Hubei 430063,China;National-local Joint Engineering Research Center of Underwater Tunnelling Technology,Wuhan Hubei 430063,China)

机构地区：[1]中铁第四勘察设计院集团有限公司,湖北武汉430063 [2]水下隧道技术国家地方联合工程研究中心,湖北武汉430063

出　　处：《公路交通科技》2021年第6期39-45,共7页Journal of Highway and Transportation Research and Development

摘　　要：随着隧道设计施工技术的快速发展,水下超大直径盾构隧道在跨越江河中日益频繁。口字件在大直径公路盾构隧道断面结构采用较多,其具有施工速度快、充分利用断面空间资源等优点,一般采用预制装配式结构,与隧道管片的连接一般采用铰接或者刚接方式,在地震荷载作用下,口字件的不同连接方式对隧道断面结构的地震内力响应不同,为了对超大直径过江隧道盾构段的抗震设计提供可靠的依据,利用ABAQUS有限元分析计算软件,考虑50 a超越概率2%地震波加速度时程曲线(重现期2475年),选取了4个代表性断面,采用时程分析法对盾构段隧道口字件部位在刚接与铰接的情况下的地震响应特征进行了计算对比研究。结果表明:在铰接的情况下,口字件部位截面的最大轴力有所减小或保持不变;当埋深较浅时,最大剪力略有减小,当埋深较深时,口字件部位最大剪力有所增大;采用铰接的情况下,最大弯矩均有所减小或保持不变,铰接部位的弯矩有显著减小,口字件部位最大变形有所减小或保持不变;从隧道抗震的角度来讲,口字件部位采用铰接的方式要优于刚接;在铰接的情况下,口字件部位轴力最大值向非铰接侧偏移,弯矩与变形的最大值向底板部位偏移,在隧道抗震设计中应对以上部位进行重点关注。With the rapid development of tunnel design and construction technology,underwater super-large diameter shield tunnels are increasingly frequent in crossing rivers.The hinged joint is widely used in large-diameter highway shield tunnels,which has the advantages of fast construction speed and full use of cross-sectional space resource.The prefabricated assembly structure is connected to the tunnel tube piece by or rigid joint.Under the action of seismic load,the different connection modes of hinged joint respond differently to the seismic internal force of tunnel section structure.In order to provide a reliable basis for the seismic design of the shield section of the super-large diameter cross-river tunnel,by using the ABAQUS FE analysis and calculation software,based on the time history curve of seismic wave acceleration with a probability of exceeding 2%in 50 years(recurrence period of 2475 years),selecting 4 representative sections,the seismic response characteristics of the hinged joint of shield tunnel under rigid and hinged connections are calculated and compared by using time history analysis method.The result shows that(1)in the case of hinged connection,the maximum axial force of the hinged joint section reduces or remains unchanged;(2)the maximum shear force slightly reduces when the buried depth is shallower,while the maximum shear force increases when the buried depth is deeper;(3)in the case of hinged connection,the maximum bending moment reduced or remains unchanged,the bending moment of the hinged part significantly reduces,and the maximum deformation of the hinged joint reduces or remains unchanged;(4)from the viewpoint of tunnel seismic resistance,the hinged connection of the hinged joint part is better than rigid connection;(5)in the case of hinged connection,the maximum axial force of the hinged joint is shifted to the non-hinged side,and the maximum values of bending moment and deformation are shifted to the bottom plate,which should be paid attention to in the tunnel seismic design.

关 键 词：隧道工程 地震响应 时程分析法 盾构隧道 口字件 

分 类 号：U452.2[建筑科学—桥梁与隧道工程]