盾构隧道下穿建筑物计算分析及对策

Calculation Analysis and Countermeasure of Shield Tunnel Crossing Buildings

为解决盾构隧道在全断面砂层中下穿高层建筑物难以控制地面沉降并可能引发建筑物安全风险的问题,以南昌地铁2号线盾构施工下穿既有建筑物工程案例为依托,采用数值模拟计算,研究采取措施的必要性,并据此提出斜向注浆加固技术,同时根据现场监测数据,研究注浆加固效果。研究认为,采用注浆加固措施有较大的实施意义,能够有效减少建筑物所受盾构下穿过程中土体扰动的影响,能够满足相关施工规范要求,可对今后的工程提供有意义的参考。

In order to solve the problem that it is difficult to control ground subsidence and possibly lead to building safety risk when shield tunnel passes through high-rise buildings in full-face sand layer,the paper is based on the case of shield tunneling under existing buildings of Nanchang Metro Line 2,using numerical simulation to study the necessity of taking measures.Based on this,oblique grouting reinforcement technology is put forward.At the same time,grouting reinforcement effect is studied according to field monitoring data.It is concluded that the grouting reinforcement measures are of great practical significance,can effectively reduce the influence of soil disturbance during the shield tunneling process,can meet the requirements of relevant construction codes,and can provide meaningful reference for future projects.