深切槽段冲刷对越江盾构隧道纵向变形影响计算  

CALCULATIONS OF LONGITUDINAL DEFORMATION FOR RIVER-CROSSING SHIELD TUNNELS INDUCED BY SCOUR IN DEEP CHANNEL SECTIONS

作　　者：李雪[1,2] 吴九七[1] 耿凤娟 耿翱鹏 张玉申 LI Xue;WU Jiuqi;GENG Fengjuan;GENG Aopeng;ZHANG Yushen(School of Geoscience and Technology,Southwest Petroleum University,Chengdu 610500,China;Shanghai Key Laboratory of Rail Infrastructure Durability and System Safety,Tongji University,Shanghai 201804,China)

机构地区：[1]西南石油大学地球科学与技术学院,成都610500 [2]同济大学上海市轨道交通结构耐久与系统安全重点实验室,上海201804

出　　处：《工业建筑》2021年第7期6-10,38,共6页Industrial Construction

基　　金：国家自然科学基金项目(51808469);上海市轨道交通结构耐久与系统安全重点实验室开放基金资助(R201902)。

摘　　要：河床深切槽段的冲刷淤积使得越江隧道纵向荷载十分复杂,影响隧道纵向变形。基于南京地铁越江隧道工程,研究不同冲刷深度、深泓位置引起的盾构隧道纵向变形行为。采用有限元建立计算模型,得到不同工况下隧道纵向的变形情况,根据变形曲线计算隧道的曲率半径和隧道环缝的张开量。结果表明:1)变形后隧道的曲率半径及环缝最大张开量与冲刷深度及冲刷范围相关,冲刷的范围越大,隧道的回弹量也越大,相应的曲率半径也越小,环缝张开量越大;冲刷深度越大,曲率半径越小,环缝张开量越大。2)环缝最大张开量位置在深泓位置附近。3)在隧道变坡点附近,环缝张开量明显大于前后直线段的张开量,设计时应尽量避免变坡点位置在深泓摆幅范围内。The scour and deposition in deep channel sections of a river bed make the longitudinal loads acting on river-crossing tunnels complicated and affect the longitudinal deformation of tunnels.Based on the river-crossing tunnel project of Nanjing Metro,the longitudinal deformation properties of the shield tunnel caused by different scoured depth and thalweg locations were studied.Firstly,the finite element model was constructed to obtain the longitudinal deformation of the tunnel in different scoured conditions.According to the deformation curve,the curvature radius of the tunnel and the opening widths between joints were calculated.The results showed that:1)The radius of curvature of the tunnel and the maximum opening widths of segment joints were related to the scoured depth and range.The larger the scoured range,the greater the rebound of the tunnel and the smaller the corresponding curvature radius,the larger the opening between segements.2)The position of the maximum opening width was near the thalweg.3)In the vicinity of change point for tunnel slopes,the opening widths of segments were obviously larger than that of constant slope sections.Therefore,the locations of changing slope for tunnels should be away from the zones of depth variation for thalwegs in design.

关 键 词：盾构隧道 纵向变形 河床冲刷 张开量 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]