盾构连续穿越浅基础民居微变形控制技术

Micro Deformation Control Technology of Shield Continuously Passing Through Shallow Foundation Residential Buildings

盾构穿越浅基础建筑物微变形控制一直是岩土工程界面临的重要难题。以杭州某软弱地层地铁盾构连续穿越浅基础建筑物工程为例,介绍了长管注浆微变形加固技术,探讨了盾构穿越浅基础民房掘进参数之间关系,提出了适用于软弱地层盾构穿越浅基础建筑物的掘进参数,分析了软弱地层盾构连续穿越浅基础民居变形特性和微变形控制技术效果。结果表明:长管注浆微变形加固技术可有效控制土层变形,减小建筑物沉降;地表沉降主要由刀盘切削土体扰动和同步注浆不到位引起,盾构穿越浅基础建筑物主要造成建筑物不均匀沉降;盾构机总推力与刀盘扭矩、土舱压力及掘进速度变化趋势较一致。最终,浅基础建筑物基本实现了“微变形”的目标。

Micro deformation control of shield tunneling through shallow foundation buildings has always been an important problem in geotechnical engineering.Taking a subway shield continuously crossing shallow foundation buildings in Hangzhou as an example,this paper first introduced the long pipe grouting micro deformation reinforcement technology,discussed the relationship between the tunneling parameters of shield crossing shallow foundation civil houses,and put forward the tunneling parameters suitable for shield crossing shallow foundation buildings in weak strata,finally,the deformation characteristics and micro deformation control effect of shield continuously crossing shallow foundation residential buildings in soft ground were analyzed.The results show that the micro deformation reinforcement technology of long pipe grouting can effectively control the soil deformation and reduce the settlement of buildings;the surface settlement is mainly caused by the disturbance of soil cut by the cutterhead and the lack of synchronous grouting;the shield passing through shallow foundation buildings mainly causes the uneven settlement of buildings;the variation trend of total thrust of shield machine is consistent with cutter head torque,earth tank pressure and tunneling speed.Finally,shallow foundation buildings basically achieve the goal of“micro deformation”.