Abstract: This paper focuses on the deep excavation project of Block Sudi 2023-WG-63, located adjacent to Heshan Station on Suzhou Metro Line No. 3. Based on the unique characteristics of deep excavation and its relative position to the metro structure, a three-dimensional simulation model was established using three-dimensional modeling software to analyze the safety impact of partitioned construction of a large and irregular-shaped excavation on the existing metro structure. The research results indicate that the deformation of the existing metro structure primarily occurs during the excavation phase, with the excavation of Area B being the most significant phase of impact. The excavation has a greater effect on the ancillary facilities of the station than on the main station structure, and the deformation is mainly vertical. Adopting a construction sequence of “deep before shallow, far before near” during excavation can effectively reduce deformation and displacement of the station structure, guaranteeing the safe functioning of the current stations and sections.

Key words: Large and Irregular Deep Excavations, Rail Transit, Station Structure, Section Structure, Numerical Simulation