Force And Deformation Analysis In Construction Process Of The GCRW Deep Excavation

Gridding Concrete Retaining Wall (GCRW) is a novel structure, which could be used in the coastal soft soil. Due to its advantages such as the large workspace, the capability of deformation control and the benefit of sustainable development, GCRW has been recently applied in several excavation cases. As a new retaining structure with the obvious spatial geometrical characteristics, the design and construction of the GCRW excavation is still a lack of experience. The analysis method of the traditional retaining structure is insufficient for this type of structure. Therefore, this new structure is limited in the application and popularization. In order to extend and develop this novel structure in deep excavation, this thesis evaluates the force and deformation of the GCRW excavation in the process of contruction, based on in-situ test and three dimensional finite element analysis. The main content of this thesis is described in the following:(1) In-situ test is used to analyze the fore and deformation in construction process of the GCRW deep excavation. A comprehensive monitoring system is installed on an unbraced excavation which is retained by GCRW. The surrounding environment and the geological conditions of the site are introduced in detail. The lateral wall deflections, vertical wall movement, ground settlement, lateral earth pressure and wall stress are the key projects in this in-situ test. Each type of the measured data is analyzed systematically and comprehensively.(2) The conclusions of the in-situ test can be used to correct the parameters of 3D model and the three-dimensional finite element model which can be used to analyze the interaction of the GCRW structure and soil is established. By using the finite element method, Force and deformation behaviors including the lateral wall deflections, vertical wall movement, ground settlement, basal heave, lateral earth pressure and bending moment of the wall due to deep excavation are investigated in details.3D effects of the force and deformation behaviors are also studied in this thesis.(3) Comparing the results computed by the 3D model and the in-situ test, it can be found that this two kinds of means show the similar rule in the force and deformation behaviors of the GCRW excavation, such as the variation and distribution characteristics of the lateral wall deflections, vertical wall movement, ground settlement, lateral earth pressure and the bending moment of the wall. Some differences can be explained reasonably and the direction of further research is put forward. Practice shows that using the method of combining the two kinds of means has a positive role for discovering the force and deformation behaviors of the GCRW excavation. The general trends provide a reference for the design and construction of the GCRW excavation.