饱和地层稳态渗流盾构开挖PIV试验研究  

PIV experimental study on steady-state seepage in saturated strata during shield tunneling excavation

作　　者：汪宇航 丁智 WANG Yuhang;DING Zhi(School of Civil Engineering and Architecture,Anhui University of Science and Technology,Anhui Huainan 232001,China;Department of Civil Engineering,Hangzhou City University,Hangzhou 310015,China)

机构地区：[1]安徽理工大学土木建筑学院,安徽淮南232001 [2]浙大城市学院土木工程系,杭州310015

出　　处：《低温建筑技术》2024年第11期91-94,99,共5页Low Temperature Architecture Technology

基　　金：国家自然科学基金资助项目(52178400,52009122);浙江省“尖兵”“领雁”研发攻关计划(2023C03182)。

摘　　要：文中以稳态渗流下盾构隧道为研究背景,通过离心模型试验,研究不同水头高度下稳态渗透下的饱和土地层盾构开挖面失稳及其地表沉降。研究基于量纲分析法和力学相似规律理论,通过对制备不同水头高度下的饱和土进行离心模型试验,从而模拟盾构开挖面失稳破坏。研究结果表明,土体变形失稳范围随着水深比(H/D)的增大不断增大。开挖至极限状态时,主要沉降影响范围为以盾构开挖面前方0.5D处为中心的2D区域内。地表沉降最大值随着水深比(H/D)的增大而大幅增加,沉降形状由“W”型逐渐变为“V”型。失稳破坏时,主要沉降影响范围为以盾构开挖面前方0.4D处为中心的2D区域内,当水头高度达到超过2D后,地表沉降最大值基本稳定,不会随水深比的增加大幅增大。沉降由不对称逐渐变为对称且沉降形状基本为“V”型。研究可为饱和地层盾构开挖的工程风险监测提供参考。This study investigates the instability of the excavation face and ground surface settlement in saturated soil layers under steady-state seepage conditions,using shield tunneling as the research background.Centrifugal model tests were conducted to explore the effects of different water head heights on the stability of the excavation face.Based on dimensional analysis and mechanical similarity theory,various saturated soil samples were prepared for the tests to simulate excavation-induced failure.The results indicate that the range of soil deformation and instability increases with the water depth ratio(H/D).At the limit state of excavation,the primary settlement impact area is a 2D region centered 0.5D in front of the excavation face.The maximum ground settlement increases significantly with the water depth ratio,changing from a'W'shape to a'V'shape.During failure,the main settlement impact area is a 2D region centered O.4D in front of the excavation face.Once the water head exceeds 2D,the maximum ground settlement stabilizes and does not increase significantly with the water depth ratio,transitioning from asymmetric to symmetric settlement,with the shape predominantly'V'.This research provides valuable insights for engineering risk monitoring in shield tunneling through saturated strata.

关 键 词：稳态渗流 饱和土地层 地表沉降 

分 类 号：TU473[建筑科学—结构工程]