Guo, C.; Guan, X.; Shi, L., and Qiu, S., 2018. The influence of earth pressure balanced shield tunnel underpassing coastal water body on stratum deformation. In: Liu, Z.L. and Mi, C. (eds.), Advances in Sustainable Port and Ocean Engineering. Journal of Coastal Research, Special Issue No. 83, pp. 237–246. Coconut Creek (Florida), ISSN 0749-0208.
The complexity of construction technology and the surrounding soil environment of shield tunnel, especially the construction of soil pressure balanced shield tunnel in soft foundation, will inevitably cause the settlement of the overlying soil stratum and surface of tunnel. When there is coastal water body on the surface above the tunnel, it will change the distribution and size of pore water pressure in the soil stratum below the coastal water body, thus affecting the settlement of the overlying soil stratum of tunnel. However, most urban subway tunnels are double-tunnel single-track shield tunnels, and successive tunnel construction will also cause the change of settlement law. In this paper, based on the analytical solution of Verruijt and Booker, combining with the principle of stratum equivalent stiffness and the distribution and action of surface coastal water body, the formula for calculating the stratum settlement caused by the construction of double-tunnel single-track shield tunnel underpassing coastal water body was derived. Taking the shield tunnel in Chaoyang Park Station-Zaoying Station of Beijing Metro Line No. 14 Project underpassing the Chaoyang Park lake body as the research object, the settlement values of the original stratum were calculated by the derived formula, and the calculated settlement values were compared with the monitoring settlement values. The results showed that the calculated settlement values were in good agreement with the monitoring settlement values, which verified the rationality and applicability of the formula, thereby providing a basis and reference for similar projects in the future.