硬岩地区盾构掘进地表竖向位移监测数据及数值模拟分析

Analysis on Surface Settlement of Shield Excavation in Hard Rock Areas by Field Monitoring and Numerical Simulation

结合杭州市某盾构掘进实际工程的地表竖向位移监测数据,总结了硬岩地区盾构掘进对周边环境的影响规律,并通过建立合适的数值模型分析了相关掘进参数对盾构掘进的影响,同时分析了不同区域浆体缺失对地表竖向位移的影响。研究结果表明:因边界条件不同、岩土不均匀性、注浆参数控制不当,硬岩地区盾构掘进仍能引起较大的地表沉降;某环掘进方向前后方浆体缺失均会对该环处地表沉降造成一定影响;后方浆体缺失时,临近4环以外浆体缺失造成影响较小,不足临近4环造成影响的10%;前方浆体缺失时,临近9环以外浆体缺失造成影响较小,不足临近9环造成影响的10%;某环掘进方向前方浆体缺失对该环处地表沉降的影响更大,约为后方浆体缺失影响的1.16倍。得到的结论可为类似工程提供参考借鉴。

Combined with the monitoring data of the ground surface vertical displacement of a shield tunneling actual project in Hangzhou, the influence of shield tunneling on the surrounding environment during tunnel tunneling in hard rock areas was summarized, and the influence of relevant tunneling parameters on shield tunneling was analyzed by establishing a suitable numerical model. At the same time, the influence of the lack of slurry in different areas on the vertical displacement of the ground surface was analyzed. The results of the study show that due to different boundary conditions, geotechnical inhomogeneity, and improper control of grouting parameters, shield tunneling in hard rock areas can cause large surface settlements. The absence of the front and rear slurry in a certain ring tunneling direction will affect the surface settlement of the ring to a certain extent. When the back slurry is missing, the impact caused by the missing slurry outside the adjacent 4 th ring is less, less than 10% of the impact caused by the adjacent 4 th ring. When the front slurry is missing, the impact of the missing slurry outside the 9 th ring is less, less than 10% of the impact caused by the adjacent 9 th ring. The lack of slurry in the forward direction of a ring has a greater impact on the surface settlement of the ring, which is about 1.16 times the impact of the lack of slurry in the rear. The conclusions obtained can provide reference for similar projects.