盾构隧道管片渗漏侵蚀的室内模型试验研究  

Laboratory Model Test Study on Leakage and Erosion of Shield Tunnel Segment

作　　者：加瑞[1,2] 李青茁 雷华阳 Jia Rui;Li Qingzhuo;Lei Huayang(School of Civil Engineering,Tianjin University,Tianjin 300350,P.R.China;Key Laboratory of Coast Civil Structure Safety of Ministry of Education,Tianjin University,Tianjin 300350,P.R.China)

机构地区：[1]天津大学建筑工程学院,天津300350 [2]天津大学滨海土木工程结构与安全教育部重点实验室,天津300350

出　　处：《地下空间与工程学报》2025年第1期171-179,206,共10页Chinese Journal of Underground Space and Engineering

基　　金：国家自然科学基金(52378362,51890911);天津市科技计划项目(21JCYBJC00380)。

摘　　要：盾构隧道管片渗漏侵蚀会改变周围土体的孔压分布,使周围土体发生变形、管片内力发生改变,影响隧道的安全运营。通过自行研制的盾构隧道管片渗漏侵蚀模拟试验装置,研究了砂土粒径、压力水头、上覆压力和砂土密实度对漏水量、漏砂量和地表沉降的影响。结果表明:(1)砂土的平均粒径越大,渗透系数越大,流速越大,过水断面相同时漏水量越大,漏砂量和试样表面的沉降量越小;(2)当砂土的平均粒径与渗漏孔径的比值较小时,砂土会持续漏出,累积漏砂量线性增大;(3)当砂土的平均粒径与渗漏孔径的比值大于0.15时,砂土颗粒在渗漏孔附近能形成稳定的土拱,砂土成拱时的平均粒径远小于渗漏孔径;(4)试样顶部的压力水头越大,水力坡降越大,流速和漏水量越大,作用在砂土颗粒上的渗透力越大,漏砂量和试样表面的沉降量越大;(5)上覆压力越大,渗透系数相对越小,流速和漏水量越小,土颗粒移动所受的摩擦阻力越大,砂土颗粒越不容易移动,因此漏砂量和试样表面的沉降量越小;(6)试样相对松散,其孔隙比和渗透系数相对较大,流速和漏水量较大,由于剪胀性较弱土颗粒相对容易发生移动,漏砂量和试样表面的沉降量较大。The leakage and erosion of shield tunnel segment will change the pore pressure distribution of surrounding soil,arise deformation of surrounding soil,and arise variation of internal force of segment,which will affect the safe operation of tunnel.The effects of sand particle size,pressure head,overburden pressure and relative density of sand on water leakage,sand leakage and ground surface settlement were investigated by a self-developed test device for simulating leakage and erosion of shield tunnel segment.The test results show that:1)The larger the average particle size of sand was,the greater the coefficient of permeability,the greater the flow rate,the greater the water leakage with the same water crossing section,the smaller the sand leakage and surface settlement of specimen.When the ratio of average particle size of sand to diameter of leakage hole was small,sand was continue to leak out,and the cumulative sand leakage increased linearly.When the ratio of average particle size of sand to diameter of leakage hole was greater than 0.15,the sand particles could form the stable soil arch around the leakage hole,and the average particle size of sand forming the soil arch was much smaller than the diameter of leakage hole.2)The greater the pressure head on the top of specimen was,the greater the hydraulic gradient,the greater the flow rate and water leakage,the greater the seepage force applied on sand particles,the greater the sand leakage and surface settlement of specimen.3)The greater the overburden pressure was,the relatively smaller the coefficient of permeability,the smaller the flow rate and water leakage,the greater the friction resistance when the sand particles moved,the harder the sand particles to move,so the smaller the sand leakage and surface settlement of specimen.4)The relatively looser the specimen was,the relatively larger the void ratio and coefficient of permeability,the relatively larger the flow rate and water leakage,the relatively easier the sand particles to move due to the weak dilata

关 键 词：盾构隧道 渗漏侵蚀 砂土粒径 压力水头 上覆压力 

分 类 号：TU43[建筑科学—岩土工程]