软土地层中盾构施工参数对地表沉降的影响研究

Study on Influence of Soft Ground Shield Tunneling Parameters on Ground Surface Settlement

为了解决软土地层中盾构隧道施工参数对地表沉降的影响问题,通过对杭州某地铁区间盾构施工进行监测,分析软土地层地表沉降的一般规律,结合该区间盾构隧道施工,采用ABAQUS有限元软件分析了注浆压力、浆液弹性模量、土舱压力等因素对地表沉降的影响。研究表明:土舱压力对地表沉降影响最大,注浆压力次之,浆液弹性模量的影响最小。地表沉降由土体塌陷沉降和土体固结沉降2部分组成,在盾构试掘进阶段对施工参数进行调整和优化,能较好地控制地表沉降。

The rule of ground surface settlement caused by shield tunneling in soft strata is analyzed, with a shield-bored running tunnel of Hangzhou Metro as example. The influence of grouting pressure, grout elastic modulus and excavation chamber pressure on the ground surface settlement is analyzed by ABAQUS. The results show that the excavation chamber pressure has the largest influence on the ground surface settlement, the grouting pressure comes the second, and the grout elastic modulus comes the third. The ground surface settlement consists of settlement induced by ground collapse and that induced by ground consolidation. The ground surface settlement can be effectively controlled if the tunneling parameters can be adjusted and optimized in the trial boring stage.