Abstract: The excavation of deep foundation pit adjacent to the existing railway in soft soil area is easy to induce the uncontrollable surrounding ground subsidence, resulting in the misalignment of the existing railway line, thus affecting its normal operation. At present, the impact analysis of the deep excavation near the existing railway in soft soil area has not attracted wide attention, and there is a lack of the correspondent design and monitoring data. In this paper, a deep excavation adjacent to the existing railway in Shanghai is taken as an example to study the influence of the deep excavation on the existing railway. The research results show that: (1) The deep excavation supporting structure near railway side should be designed according to the deformation control and increasing supporting stiffness to reduce the settlement of the railway subgrade; (2) With the excavation of deep foundation, the settlement rate curve of the railway subgrade first increases and then decreases, and the final settlement is large; (3) This paper can be used as the reference for the similar design and construction of deep foundation adjacent to the existing railway.

Key words: Deep Excavation, Soft Soil, Existing Railways, Subgrade Settlement, Numerical Analysis