Yield Criterion And Finite Element Analysis For Soil Nailing Wall

With the development of industry and municipal construction,ground surface is becoming less and less. As a kind of still unexploited resources, underground is attracting more attentions and being widely utilized for underground establishments as sub-carport, sub-marketplace and subway, etc. As a result, the depth of excavation is becoming deeper. Soil nailing wall is finding its wider application in foundation engineering for its outstanding profits and favorable working characters, therefore they have been studied theoretically by lots of scholars. Yet the mechanism and genuine character for composite soil nailing wall is still left unclear, demanding further research.Yield and failure behavious of rock and soil masses were analyzed from the mechanical meanings. The intuitionistic explanations of the mechanism for formation of critical slip surfaces in slopes were given by adopting Mohr-Coulomb's falure criterion and tension-shear composite failure criterion respectively. Based on the current studies of the behavior and mechanism of the structure, take advantage of software ANSYS ,the composite soil nailing wall were analyzed systematically with the FEM and the elastic-plastic theory in order to meet the need in engineering. And some valuable conclusions are obtained, which can be taken as references in design and construction.(1) Yield and failure behavious of rock and soil masses were analyzed from the mechanical meanings. The intuitionistic explanations of the mechanism for formation of critical slip surfaces in slopes were given by adopting Mohr-Coulomb's falure criterion and tension-shear composite failure criterion respectively. tension-shear composite failure criterion was introduced into the analysis of the soil nailing wall, safety factor which was calculated by using tension-shear composite failure criterion was compared with the Code of Soil-Nailing on Foundation Pit (96:97) and Technical Code of Soil on Building Foundation Pit (JGJ120-99) by taking the example of a soil nailing wall.(2) The stress location, displacement of soil, axial forces of nail, displacement of soil-cement mixing piles of composite soil nailing wall were analyzed with the staged excavation in this paper.(3) The paper has a further research on the influence of composite soil nailing wall behavior in the perspective of the effect of the length of nails, the angle of nails, the stiffness of soil-cement mixing piles.(4) In contrast of the structure behaviors in the staged excavation between the soil nailing wall and the composite soil nailing wall and with the analysis of various effecting factors on composite soil nailing wall, the paper holds a deep analysis of the mechanism's essence of the composite soil nailing wall.