Numerical Simulation Analysis Research On Affection Factors Of Soil Nailing Deformation

With the utilization and development of high-rise buildings and underground space, foundation pit projects inpractical are increasing. Traditional soil nailing has already been widely applied in the supporting systems of foundation pit, Composite soil nailing is a new, flexible, widely applied geotechnical integrated supporting structure, which inherits and develops the traditional soil nailing technique, this technique overcomes much defect of traditional soil nailing, so it has a broad developing prospects. The current design bases mainly stability contract of foundation pit, and there is no mature theoretical for calculation of the lateral deformation of support structure. The design mainly depends on the experience and engineering analogy.The theories of the deformation of the foundation pit lagges behind the engineering practice. The whole procedure of the staged excavation and retaining on composite soil nailing is simulated by use of engineering case and numerical simulation, and then variable laws of displacement of slide slope is discussed and comparied traditional soil nailing to composite soil nailing in the paper. Contents are mainly showed as follows:The basic features and the computable principles,the building of the model and the choise of the structure element of the FLAC-3D is introduced,meanwhile the feasibility of simulation to the characteristic of the retaining structure elements is proved. The numerical model of a project was builded by using of FLAC-3D. Based on the project data and according to simulated data. The Lateral displacement and their variety regulation with the excavation is analysed in this paper.The orthogonal experiment method is applied in the analysis of foundation pit,11 factors to soil nailing supporting of Lateral displacement is studied. With regard to various parameters of the soil nailing the influence to the lateral deformation of the soil nailing was studied,which includes the disposal,inclination angle,the length and spacing of the soil nailing.The engineering case of advanced micro-pile and soil nailing,pre-stressed anchor and soil nailing,cement mixing pile and soil nailing are sudied by numerical simulation, characteristics of support stuctural displacement is analysed systematically for three type of composite soil nailing and then variable laws of displacement of slide slope is dicussed traditional soil nailing is compared with composite soil nailing about lateral deformation.