Abstract: Due to the lack of available for the construction in urban area, large scale deep excavations in densely populated, closely adjacent to existing buildings and streets are common for the construction of metros, underground parking garages and underground shopping centers. To minimize the adverse effect induce from the deep excavation, the deformation of the supporting structures should be closely monitored. This paper summarizes the excavation supporting types encountered in the construction inspection projects and their deformation characteristics. Both advantages and disadvantages of each supporting type as well as their applicable conditions are introduced in the paper.

Key words: Soft Soils, Deep Excavations, Supporting Structures, Deformation Monitoring