富水地层盾构下穿城市快速路隧道影响分析

An Analysis of the Impact of Shield Tunnel on Silt Strata Under Urban Expressway Tunnel

以常州市地铁1号线工程为应用背景,利用有限元软件数值计算模型和实测数据,研究了盾构隧道施工对城市快速路隧道的影响规律。数值计算结果表明:富水地层中盾构下穿城市快速路隧道时,结构处于安全状态。现场实测数据分析表明:盾构掘进引起的实测沉降,其横断面沉降呈漏斗型,与Peck公式形态相似;双线掘进引起结构沉降最大值位置由单线隧道中心位置向双隧道中心位置偏移;三轴搅拌桩预先加固有效提高了结构的抗变形能力。

Shield tunneling through structures has become a difficulty in subway engineering construction.In this paper,taking the Changzhou Rail Transit Line 1 project as the application background,a numerical analysis model is established to analyze the impact of shield tunnel on silt strata under urban expressway tunnel.The engineering measured data is also analyzed.The numerical calculation results show that the structure is in a safe state when the shield tunnel passes through the urban expressway tunnel in the water-rich stratum.The cross-section settlement caused by shield tunneling in field is funnel-shaped,similar to the form of Peck formula.The maximum position of the structural settlement caused by the two-way tunneling is shifted from the center position of the single-line tunnel to the center position of the double tunnels.The research results show that the pre-reinforcement of the triaxial mixing pile effectively improves the structural resistance to deformation,and the safety of the shield passing through the structure is significantly increased.