The Application Research Of SMW In Deep Foundation Pit Support

The stability and safety of foundation pits have always been the key points and difficulties in the construction of underground space structures.The irregular shape of the foundation pits of the auxiliary structures and the different excavation depth also make the situation is variable,The foundation soil within the influencing depth of the foundation pit of this project is mainly composed of miscellaneous fill,silty soil and silty clay,with complex composition and loose structure.There are construction waste such as broken bricks and stones on the surface.Some sections are rich in plant roots and are close to the water source.The above factors will affect the construction quality of the foundation pit support structure to a certain extent and be unfavorable for maintaining the safety of the foundation pit and the surrounding environment and may result in a large deformation of the foundation pit.Deep foundation pit support design is a design project for which many factors need to be considered.With the development of support methods,many foundation pit support methods have also been developed.Each has its own characteristics and certain commonalities and also certain differences with other methods.Therefore,with the analysis of the applicability of different supporting methods,and according to the actual conditions of the construction site of this project,the SMW construction method is considered as the most suitable method for the actual site conditions.With the deep foundation pit support project of the Weiwei Group L7～4 block in Xuzhou area being taken as a case,the parameter calculation and design theory of the SMW foundation pit support method was studied.Through the site survey of this project,the shape steel section and spacing in this support method was calculated,the stability of the support structure was checked,and the entire construction process was monitored,determining the design scheme is consistent with the actual situation on site.The deep foundation pit support was numerically simulated by Midas numerical simulation software.Through the analysis of the simulated cloud diagram of the supporting structure of the constructed model,the pile displacement of the supporting structure was obtained,and the ground surface settlement,bending moment value and shearing force around the supporting foundation pit were all determined as within the design range,having provided theoretical reference for the implementation of the support project of the foundation pit.The applicability and advancement of SMW construction method in this project have been verified in this project,which can provide reference for similar projects in the future.