岩土工程学报2026，Vol.48Issue(3)：655-665,11.DOI:10.11779/CJGE20240317
富水卵石砂土地层盾构穿越立交桥桩基群施工力学行为研究
Study on tunneling construction mechanical behavior of pile foundation group for shield structure crossing overpasses in water-rich pebbly sand stratum
摘要
Abstract
This study investigates the mechanical behaviors of pile foundation underpinning and shield tunnel construction in water-rich pebbly sand stratum,using the Chengdu Metro Line 13 shield tunnel at the Jiaozi Overpass as a case.First,large-scale direct shear tests are conducted on pebbly sands at three water contents(2%,12%,22%)in air-dried,natural,and saturated states.Subsequently,numerical simulations are used to analyze the deformation and force mechanisms during pile foundation underpinning and shield tunnel construction.Finally,deformation control measures for pile foundations and tunnels are proposed.The simulation results are validated against field monitoring data.The results show that the shear strength of pebbly sands decreases with increasing water contents.The cohesion and internal friction angle of saturated pebbly sands are 62.5%and 82.8%lower than those of air-dried pebbly sands,respectively.The air-dried and natural pebbly sands show dilatancy,while the saturated pebbly sands show contraction.After pile foundation underpinning,the axial force of the pile is significantly reduced.Following shield tunneling,the axial force of the pile near the tunnel increases significantly,while higher water content reduces lateral friction resistance and increases pile settlement.Pile foundation settlement is primarily caused by pile foundation underpinning and shield tunnel construction.The settlement induced by pile foundation underpinning accounts for 73.2%-96.8%of the total settlement,with the calculation results closely matching the field measurements.Tunnel vault settlement is influenced by water content.When the water content of the pebbly sand layer is controlled around 12%,the proposed control measures can effectively limit the settlement of both the bridge and tunnel.关键词
富水卵石砂土地层/大型直剪试验/桩基托换/盾构穿越/力学行为Key words
water-rich pebbly sand stratum/large direct shear test/pile foundation underpinning/shield crossing/mechanical behavior分类
建筑与水利引用本文复制引用
王毅,卢锋,张俊儒,孔超,雷沙沙,吴城..富水卵石砂土地层盾构穿越立交桥桩基群施工力学行为研究[J].岩土工程学报,2026,48(3):655-665,11.基金项目
国家自然科学基金项目(52408440,52108385) （52408440,52108385）
四川省自然科学基金项目(2024NSFTD0008) （2024NSFTD0008）
中铁四局集团有限公司委托课题(2021-38)This work was supported by the National Natural Science Foundation of China(Grant Nos.52408440,52108385) （2021-38）
the Sichuan Provincial Natural Science Foundation(Grant No.2024NSFTD0008) （Grant No.2024NSFTD0008）
and a commissioned project by China Railway Fourth Bureau Group Co.,Ltd.(Grant No.2021-38). （Grant No.2021-38）
