Abstract: During the deep excavation, the stress state of the surrounding soil is changed, causing displacement and structural deformation in the underlying shield tunnels, which might compromise their operational safety. Through a case study of a deep excavation in Hangzhou, the spatiotemporal effects during excavation is considered and the excavation adopted the zoning and block excavation principle of “large excavated area, small excavation.” The excavated bottom slab was surcharged, and this method is the effective technical measures to control deformation in the underlying tunnels, which can effectively achieve the goal of safety control in adjacent construction. Additionally, the finite element numerical model can simulate the actual construction conditions throughout the entire process. The results reveal the necessity of finite element analysis and the rationality of the computational model, providing valuable references for the optimized design and construction of similar projects.

Key words: Adjacent Construction, Deep Excavation, Underlying Tunnel, Deformation Effects, Finite Element Analysis ,