Abstract: As the results of overloading around the deep excavation area, water table fluctuation and the low supporting strength of the excavation support system, failures are often occur in the soft soils during the construction. This paper analyzes the failure modes of the deep excavation supporting system from the geological conditions, support scheme and loading conditions. Following the concept of control the failure first and mitigate the problem later, the guidelines for the emergency reaction, including the strengthening the supporting system and adjustment of the earth work inside the excavated area. The construction management aspects of the deep excavation are also introduced in the paper.

Key words: Deep Excavation Support, Soft Soil Area, Failure Analysis, Mitigation Measures