Finite Element Analysis Of Damaged RC Columns With Pre-tension Steel Hoops

The serious damage and collapse of reinforced concrete structures will be occurred under the earthquake load.To maintain the collapse safety of structures,the seismic design the of the whole reinforced concrete structure is necessary.Due to the proper seismic design,most of reinforced concrete structures will not collapse under the earthquake load.However,those uncollapsed reinforced concrete structures may have different degrees of damage,which may make the structures collapse under the aftershock effects.Moreover,due to the adjustment of seismic design codes,the seismic performance of many existing buildings will not satisfy the requirements in the current seismic code.Therefore,to solve those problems,the seismic performance of RC columns with pre-tension steel hoops is studied in this research.The details of research are as follows:(1)?The seismic performance of damaged/undamaged RC column with pretension steel hoops is studied in this research.To evaluate the enhanced effect of pretension steel hoops,the failure phenomenons of all specimens is analyzed.Moreover,the numerical test results are also analyzed in this researchs;the seismic performance parameters such as hysteresis curves,ductility coefficient and strain are compared.In addition to this,the enhanced effect of pre-tension steel hoops on RC columns under different damage rates and aixal load ratios are also studied.(2)?The plastic hinge length of specimens is also analyzed in this research.Based on the comparsion of the different calculaton model about the plastic hinge,the calculation model which can accurately reflect the plastic hinge length of different specimens is seclcted.Moreover,the analyze of plastic hinge length in specimens also provide theoretical basis for the enhanced design of pre-tension steel hoops.(3)?The Mender constrained concrete constitutive relation model is introduced in this reserach.Based on the failure phenomenon and test results of specimens,the concrete constitutive relation model of RC columns with pre-tenson steel hoops was conducted.(4)?The finite element analysis software was used to simulate and analyze the nolinear behavior of sections in RC column with pre-tension steel hoops.Based on the comparison between the calculation results and the test results,the variation of the seismic performance of the specimens under different parameters such as damage amount,different size and different axial load ratios are analyzed.(5)? The numerical simulation model of hysteretic analysis of low prestressed steel hoop damage and undamaged RC column was establish ed by using the open engineering simulation system(OpenSees).Based on the comparison with the test results,quantitative analysis of the effects of different reinforcement methods,different damages and different dimensions on the seismic behavior of the specimens.(6)? The vulnerability analysis of the frame structure with LTSH-reinforced specimens was carried out.The comparison of the frame vulnerability curves showed the influence of LTSH reinforcement on the seismic performance of the overall structure.