Deformation Monitoring Analysis of Shallow Buried Pipe Jacking in Soft Soil

WANG Weizhi; LIU Wenzhuang; LI Chaohuang; XU Yongfu

Abstract：This study was conducted to monitor and analyse the displacement,soil pressure,and numerical changes in excess pore water pressure of the surrounding soil during the construction of a shallow buried pipe jacking project on Zhenxi Road of the newly built South Liaison Line in Shanghai.The monitoring was carried out by burying corresponding instruments in the soil.The study revealed the disturbance law of shallow buried pipe jacking around the pipe in soft soil.The results demonstrate that the surface settlement caused by pipe jacking construction exhibits uneven settlement in the longitudinal direction.The overall trend shows that the closer the distance from the axis of pipe jacking,the larger the settlement is,and the settlement rate reaches its maximum before and after the head of pipe jacking machine crossing the head.The degree of disturbance to the surrounding soil during pipe jacking construction is found to be related to the distance from the pipe jacking machine head to the monitoring section and the axial distance between the measuring point soil and the pipe segment.As the distance between the machine head and the monitoring section decreases,there are notable alterations in the soil pressure,pore water pressure,and horizontal displacement of the soil on the pipe side at each measuring point.Upon the passage of the pipe jacking machine head through the monitoring section,the magnitude of all observed changes is markedly diminished.The degree of disturbance to the surrounding soil is inversely proportional to the distance from the pipe jacking machine head to the monitoring section.