FEASIBILITY OF SHIELD JUNCTION USING FREEZING METHOD IN QIONGZHOU STRAIT TUNNEL

Qiongzhou strait cross-sea project has attracted a lot of attention. Of all the plans discussed, the tunnel scheme is a potential one. Because of the long distance and great depth, Qiongzhou strait tunnel has many engineering problems. AGF (artificial ground freezing) has been widely used in many tunnels as a ground strengthening method. The feasibility of AGF in construction of Qiongzhou strait tunnel was studied by using finite element numerical simulation method. The simulation was conducted to compare different freezing plans, i.e., single-row-piped freezing and the double-row-piped freezing. In the simulation, different length of cutter head in circumferential direction was demolished, affecting the mechanical behavior and deformation of the frozen soil umbrella. The research demonstrates that the double-row-piped freezing is superior to the single one on safety. The length of cutter head demolished in circumferential direction has great influence on the mechanical behavior and deformation of the frozen soil umbrella. Guidance on construction can be obtained from the layout of this paper.