Displacement Prediction Of Diaphragm Wall In Deep Excavation On Soft Clay

With the development of economy and the improvement of society, utilization of underground space has become the important field in the city construction. With the predominant performance of the diaphragm wall, it is a high using value construction technologies. It can used as main body structure (or part of the structure), as the structure waterproofing of underground slurry, also the earth retaining wall structure.Construction of diaphragm wall will arouse the horizontal stress of the soil, the displacement and the volume deformation of the soil. The building nearby will become inclining, cracking even breakdown, with the soil displacement behind the wall and the surface settlement. Soil deformations, water level descents and collapses caused by diaphragm wall construction, for the reason of passing through under the buildings and the underground pipeline systems will affect the above municipal facilities and buildings seriously. So it is important to monitor the behavior of the surrounding soil while the diaphragm wall construction period. Those data will help to validate or adjust the design parameters.This paper presents detailed information about the construction of the metro station, the key construction technology, and the main construction process and construction effects in open-excavation. Firstly, this paper makes a careful study of the engineering environment, engineering hydrogeology condition of the metro station. Then, the pumping construction technology of deep foundation pit in soft clay area is presented, the foundation well in every parts were reasonably distributed and constructed; at last the theory of time-space effect was adopted to guide the process of excavation earthwork and propping up. The emergency measure in construction of foundation pit was also put forward. Finally, through the construction monitoring and information management technology, it has been evaluated how the excavation can effect the diaphragm wall's side displacement, what is the relationship between the support forces and the side displacement of the wall, and finally how the water pumping during construction can effect the ground settlement. According to this, based on FEM (Finite Element Method) and the results of the concrete diaphragm engineering illustration, we expect with using computer software, to get a simulation of excavation process. Compared to the results of tests in situ, it validates the analysis model and method.