Numerical Simulation And Application Research On Composite Soil-nailed Wall

In recent years, soil-cement mixing piles have been developed from construction sites. As anefficient supporting system, although this kind of combined supporting system is widely used indeep foundation engineering, the complexity of its soil nailing supporting mechanism hasbeen a great obstacle for engineers to form a systematic research on it. The research towardthis kind of combined supporting system is still lacking in China and abroad.Major intention of this articles is to analyze the application of the supporting combinedwith soil nailing and the soil-cement mixing pile in actual construction with the FEM;according to the actual measuring data from a great deal of experiments and the solution andanalysis on the model established by a large finite element analysis software. The paper usesthe Drucker-prager non-linear E-B model as the constitutive model of sail;chooses the MisesIdeal elastic-plastic model which is independent of hydrostatic pressure for the nails andsoil-cement mixing piles;And analyses the stress location, displacement of soil, axial forcesof nail, displacement of soil-cement mixing piles of compound soil nailing with the stagedexcavation. And try to figure out the analysis and the computation methods to match this kindof combined supporting system, and what's more, we can provide the locale construction witha theoretical guarantee.The research focuses in this dissertation are as follows:(1)The maximum horizontal displacement is located in middle of the wall, and themaximum vertical displacement is located in the middle of the upside load.(2)In the "soil-cement mixing piles + composite soil nailing ",the maximum positivemoment of the soil-cement mixing piles is distributed in the middle of the wall of pit,thenegative one keep close to the ground ,and the maximum shear stress is distributed on thesurface .(3)The maximum nail tension forces occur at the top of the nails at initial stage as thenails have been placed into slope soil, and shift backward in the process of excavation.(4)In contrast of the structure behaviors in the staged excavation between the soil nailingand the compound soil nailing and with the analysis of various effecting factors oncompound soil nailing, the paper holds a deep analysis of the mechanism's nailing essence ofthe compound soil nailing.