盾构小曲线半径下穿注浆加固建筑群分析

盾构机掘进过程对周围建筑物、管线及道路的影响归根到底是隧道周边土体扰动造成的。本文以石家庄地铁三号线水上公园站-柏林庄站区间350 m半径小曲率转弯下穿预注浆加固建筑物为例,通过监测盾构机转弯过程中土体的分层竖向变形及水平位移数据,研究其规律及特点,同时对比直线段及曲线段特征规律。盾构机掘进过程中对土体扰动的最大沉降量为4 mm,最大上拱量为20 mm,外侧水平位移为3.9 mm,内侧水平位移为2.7 mm。结果表明,在小曲率半径转弯段,地基预注浆加固隧道周围土体仍易产生较大上拱,影响隧道施工安全,应采取有效措施进行预防。本研究可为盾构机在小曲率半径条件下通过预加固地段施工提供指导和借鉴意义。

Analysis on Grouting Reinforced Buildings for Shield Machine Under Passing in a Small Curvature Radius

The influence of the shield tunneling process on surrounding buildings,pipelines and roads is caused by the disturbance of the soil around the tunnel.With a small curvature radius of 350m between Water Park Station and Berlinzhuang Station on Shijiazhuang Metro Line 3,passing through a pre-grouting reinforced building,by monitoring the layered vertical deformation and horizontal displacement data of the soil during the turning of the shield machine,the laws and characteristics are studied,and the characteristics of the straight and curved sections are compared.The maximum settlement of soil disturbance during the excavation of the shield tunneling machine is 4 mm,the maximum amount of arch is 20 mm,the lateral horizontal displacement is 3.9 mm,and the internal horizontal displacement is 2.7 mm.The results show that in the small curvature radius turning section,the soil around the foundation pre-grouting reinforced tunnel is still prone to generate large arches,affecting the tunnel construction safety,and effective measures should be taken to prevent it.This study can provide guidance and reference for shield machine construction in pre-reinforced sections under conditions of small curvature radius.