小净距盾构隧道施工变形控制数值模拟研究

Numerical Simulation of Deformation Control of Small Clearance Shielded Tunnel Excavation

小净距盾构隧道施工会引起土体较大的应力状态变化和地层变形,当变形过大时会影响隧道结构和既有建构筑物的安全。以雄安新区某小净距隧道施工区间段为依托,建立小净距盾构隧道施工变形控制数值模型,深入研究小净距盾构隧道施工下不同控制措施对既有土层变形程度。结果表明:对于小净距叠交盾构隧道施工,注浆加固一般是最为有效的控制措施,能够显著降低地表沉降,确保工程稳定和安全。研究成果可为相关工程实施提供理论支持。

The small clearance shielded tunnelling can cause a large change in the stress state in the soil mass and deformation of the ground,which can affect the safety of the tunnel structure and existing buildings when the deformation is excessive.How-ever,the existing studies on the shielded tunnel reinforcement control measures for the small clearance shielded tunnel excava-tion are relatively insufficient,especially in the deformation control methods for the small clearance shielded tunnel excavation.In this paper,based on a small-clearance tunnel construction section in Xiong'an New Area,a numerical model of the deforma-tion control measures for the small clearance shielded tunnel excavation is established,and the effects of different reinforcement schemes are discussed in depth.The results show that the grouting reinforcement is the most effective control measure for the small clearance overlapping shielded tunnel excavation,which can significantly reduce the surface settlement and ensure the sta-bility and safety of the project.This study provides a strong theoretical support for the implementation of related projects.