Analysis of Surface Settlement Caused by Rectangular Pipe Jacking in Hefei Old Clay Stratum

Research purposes：Rectangular pipe jacking method has been widely used in engineering in recent years because of its advantages of high effective space utilization and shallow soil cover. Based on the example of Yaoyuan Road Station No. 1 and No. 2 rectangular pipe-jacking crossing entrance project，this paper analyzes the ground surface settlement and deformation law caused by pipe-jacking construction in Hefei-old clay stratum by using random medium theory，Plaxis finite element analysis and engineering site monitoring methods，and provides reference for similar projects.Research conclusions：（1）Pipe jacking in the Hefei-old clay stratum mainly caused the settlement of the upper stratum，which was mainly caused by the building gap between the pipe joint and the soil.（2）With the driving of pipe jacking，the surface settlement presents the characteristics of a slow increase at first，then a sharp increase，and finally tends to be flat. The main influence range of pipe jacking construction is divided by the excavation face，and the influence range of the front is about 3z0，and the influence range of the rear is about z0.（3）The transverse surface settlement is basically symmetrical with the center line of the pipe jacking as the axis，and the influence range is about 2z0 on both sides of the center line.（4）The research results can provide a basis for the design and construction of rectangular pipe jacking in old clay strata. © 2024 Editorial Department of Journal of Railway Engineering Society. All rights reserved.