Abstract: The deformation and stability of an excavation support structure under an expressway bridge viaduct will like directly affect a safe operation of adjacent piers and other structures nearby. A box culvert to be construction would be very close to the bridge viaduct piers No.5 and No.6. This box culvert would be constructed in a complicated and constrained environment with small vertical clearance and it would affect the safety of the bridge if an appropriate protective measure was not implemented. The stress and deformation of the excavation supporting structure were analyzed through a commercial finite element method software MIDAS-GTS. Further, the deformation of the bridge pier during the entire excavation process was simulated by FLAC3D software after the supporting structure was installed. So that the role of supporting structure could be appropriately evaluated. Throughout the evaluation of the safety and the stability of the evaluation of the deep excavation supporting structure for the box culvert construction, the results and experience can provide an important theoretical support for the design and validation of the deformation and stability of deep excavation near the active under highway, and also provide reference for similar projects in the future.

Key words: Deep Excavations, Deformation, Stability