Practices of supporting technology for shallow super-large excavations in coastal area under soft foundation conditions

Because of the low strength, high moisture content, high compressibility and marked rheology of sullage soft soils, the risk of excavating foundation pits in soft foundations is large. The option of support schemes has obvious effect on cost, progress and quality of projects. Sometimes it even becomes the key to the successful completion of the projects. Combined with the engineering practices of four super-large excavations in Pujiang Town of Shanghai, the characteristics of sullage soft soils in coastal areas of Shanghai are introduced, and the application effects of common supporting structures are also comprehensively analyzed and compared. The experience and conclusions may be helpful to the similar or even larger projects in the future.