隧道暗挖法施工诱发地层变形离心模型试验研究  

Centrifugal model tests on the mechanism of ground collapse induced by tunnel excavation method construction

作　　者：王建德 谭佳 李波[3] 刘志方[4] 梁柱 Wang Jiande;Tan Jia;Li Bo;Liu Zhifang;Liang Zhu(Guangdong Institute of Safety Production Science and Technology,Guangzhou 510060,China;Guangzhou Metro Construction Management Co.,Ltd.,Guangzhou 510000,China;Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources,Changjiang River Scientific Research Institute,Wuhan 430010,China;Guangzhou Urban Planning Survey and Design Research Institute Co.,Ltd.,Guangzhou 510060,China)

机构地区：[1]广东省安全生产科学技术研究院,广州510060 [2]广州地铁建设管理有限公司,广州510000 [3]长江科学院水利部岩土力学与工程重点实验室,武汉430010 [4]广州市城市规划勘测设计研究院有限公司,广州510060

出　　处：《工程勘察》2025年第3期1-8,共8页Geotechnical Investigation & Surveying

基　　金：国家自然科学基金项目(51308067);中央级公益性科研院所基本科研业务费(CKSF2023327/YT);2023广东省级灾害防治及应急管理专项资金项目.

摘　　要：隧道暗挖法在地铁工程建设中经常采用,但施工中易引起地层损失,尤其在软土等复杂地层区域可能导致地面塌陷。开展2组暗挖法施工过程对上覆土层变形影响的离心模型试验,研究两种不同开挖速率条件下地基顶面沉降、断面位移场、土压力的变化特征和分布规律。试验监测得到开挖进尺1m/d时,隧道中心断面沉降速率约1.4mm/d,最大沉降39.1mm,引起隧道外侧土压力增幅150kPa,模型断面位移场表明隧道中心线处地表沉降最大而两侧沉降逐渐减小;开挖进尺增大至2m/d时,隧道中心断面沉降速率增大至3.2mm/d,最大沉降52.4mm。对比分析表明,开挖进尺速度显著影响地表沉降速率和总沉降量,开挖进尺较快时,地面沉降速率越大,最大沉降值也越大;开挖引起的隧道顶部土压力的变化形象揭示了隧道顶部拱效应的存在,随着拱顶塌陷变形区域的增大,拱效应半径也逐渐增大,从0.8倍隧道宽度增大至1.7倍隧道宽度。Undercutting method of tunneling is widely adopted in subway engineering construction.However,ground loss is easily caused during construction,especially in soft soil,which may lead to ground collapse.Two sets of centrifugal model tests were conducted to investigate the influence of the construction process of the hidden excavation method on the deformation of the overlying soil layer.The variation characteristics and distribution patterns of the ground settlement above the tunnel,section displacement field,and soil pressure under two different excavation rates were analyzed.According to the monitoring,when the excavation rate is 1m/d,the settlement rate of the central section of the tunnel is about 1.4mm/d,with a maximum settlement of 39.1mm,the soil pressure outside the tunnel increases 150kPa,the displacement field of the cross-section obtained through real-time monitoring of the model crosssection shows the maximum surface settlement occurs at the centerline of the tunnel,while the settlement on both sides decreases gradually.When the excavation rate increases to 2m/d,the settlement rate of the central section increases to 3.2mm/d,and the maximum settlement is 52.4mm.Comparative analysis shows that the excavation rate significantly affects the surface settlement rate and total settlement,the faster excavation is,the larger the ground settlement rate occurs and the greater the maximum settlement is.The contour lines of the cross-sectional displacement field and the changes in soil pressure reveal the existence of the arch effect at the top of the tunnel.As the deformation area of the arch collapse increases,the radius of the arch effect gradually increases,which is from 0.8 to 1.7 times the width of the tunnel times.

关 键 词：地铁隧道 浅埋暗挖 地表沉降 塌陷 离心模型试验 

分 类 号：TU43[建筑科学—岩土工程]