包头地下综合管廊矩形顶管施工关键技术及地表变形特征

Study on key construction technology and surface deformation characteristics of rectangular pipe jacking of the comprehensive underground pipe corridor in Baotou

基于现场监控量测数据,针对矩形顶管管廊隧道在砾砂地层中关键施工技术及顶进过程中地表变形规律进行了研究.结果表明:顶进过程中地表变形以隆起变形为主,最大隆起值为36.4 mm左右,隆起范围为40 m,随后地表变形值回落到15 mm并保持稳定;矩形顶管顶进过程中引发的地表纵向变形分别为为缓慢隆起阶段、快速隆起阶段、沉降阶段和稳定阶段;地表横向隆起槽左右呈非对称状态,主要由于开挖面左右部土仓压力不对称导致.

Based on on-site monitoring and measurement data,the key construction technology of rectangular pipe jacking tunnel in gravel sand stratum and the law of surface deformation during jacking were studied.The results show that the surface deformation during the jacking process is dominated by uplift deformation,the maximum uplift value is about 36.4 mm,the uplift range is 40 m,and then the surface deformation value drops to 15 mm and remains stable;The longitudinal deformation process caused by the rectangular pipe jacking can be divided into the four deformation stages as follows:slow uplift,rapid uplift,settlement and stabilization;The transverse uplift grooves of the surface are asymmetrical on the left and right,which is mainly caused by the asymmetry of the pressure of the earth silo on the left and right of the excavation surface.The research results may provide references for similar rectangular pipe jacking projects.