Study On Numerical Stimulation Of Seismic Behavior Of RC Columns Strengthened With Prestressed Steel Wire Mesh And Polymer Mortar

The reinforcement technology of high strength prestressed steels wire mesh and high performance mortar is a new reinforcement technology,has the characteristics of high-strength,fire-resistance,corrupt-protection,convenient construction and extensive application etc.At present,the study of reinforced concrete beams,reinforced concrete board,reinforcement node and brick wall with high strength steels wire mesh and high performance mortar at home and abroad are relatively perfect,and the research on seismic behavior of reinforced concrete square columns strengthened with high strength prestressed steels wire mesh are less;and have not systematically analyse the influence factors of the seismic behavior of square columns,the ductility of prestressed reinforcement formula fitting square column can be deeply studied.Based on the seismic test by of reinforced concrete column strengthened with high strength prestressed steels wire mesh and high performance mortar,this paper establish numerical model of reinforced columns using ABAQUS,choose respective material constitutive model,on the premise of good agreement between the results of the finite element simulation and the experimental results,then analysis the influence of the parameters of prestress level,the axial compression ratiothe and the steel strand spacing on the seismic behavior of reinforced concrete columns.Refining parameters on the basis of analysis,furthermore analysis the influence of seismic parameters to reinforced columns.Finally based on grey system theory,this paper to use the above-mentioned analysis results to calculate the highest influence factor association degree,and build the BP neural network predicting model based on the grey correlation analysis for forecasting the displacement ductility coefficient of the reinforcement columns,and a approximation formula of the displacement ductility coefficient of the reinforcement columns is proposed.Through the above research work,the following major conclusions:(1)through the use of reasonable material constitutive model and based on the ABAQUS software environment,it is shown that the finite element model can be used for further factors analysis;(2)the aseismic performance of the reinforced specimen is obviously improved that of the unreinforced specimen,the displacement ductility coefficient and peak load of the reinforced concrete columns increased by 5%~57% and 21%~74%,under the different prestress level,axial compression ratio and steel strand spacing,the displacement ductility coefficient of thereinforced specimens are 1%~46%,5%~57%,28%~46% greater than the reinforced specimens,the peak load of the reinforced concrete columns are 21%~74%,27%~39%,21%~49% greater than the reinforced specimens;(3)the influence factor association degree in different prestress level,axial compression ratio and steel strand spacing are 0.650,0.818 and 0.860 by use the above-mentioned analysis results,the BP neural network prediction model based on grey correlation analysis can be used to predict and evaluate the seismic performance of reinforced columns,comparing with experimental data,the calculation results of the fitting formula of the displacement ductility coefficient is safe,and provide theoretical basis of the design and application of actual engineering.