Abstract: The deformation characteristics of the long and large sized foundation excavation with various types of excavation supports in soft soil areas are analyzed in this paper. The construction monitoring data of the soil settlement, the retaining structure deformation, and the axial force of the bracing system are collected for a project in Hangzhou. The long and large sized foundation excavation retaining structure under different support types was comprehensively analyzed and evaluated. The results show that both bored piles and the SMW method columns can effectively control the deformation of the excavation. The deformation control capability of the enclosure structure under the combined application of different foundation support types presents a strong uniformity and the deformation of the enclosure structure on both sides of the junctions is continuous. The combined application of different foundation excavation support types can meet the design and construction requirements, and the structural deformation of the foundation excavation can be controlled within the scope of the code requirements. The engineering practice can provide a construction experience and the practical basis for similar projects in the future.

Key words: Foundation Excavations, Soft Soil Area, Monitoring and Analysis, Types of Supports, Combined Applications