Research On Seismic Behavior Of Reinforced Concrete Square Column Strengthened With BFRP

The fiber reinforced composites(FRP)is a new type of high performance material.Because of its excellent mechanical properties,effective reinforcement effect and good economy,it has been applied to seismic retrofitting of engineering structures.At present,the research of FRP in China is mainly concentrated in the seismic strengthening of CFRP,relatively little research for seismic strengthening of BFRP,but its good ductility,favorable corrosion resistance and excellent economy,let it become one of the key subjects in the field of seismic reinforcement research at the present stage.A pseudo static test was carried out for seven columns reinforced with FRP and one comparative column.Through the comparison of reinforced concrete column failure phenomenon,and the analysis of load deformation curves of the specimens,the seismic performance of reinforced concrete columns under different reinforcement was discussed.The test results show that BFRP plays a good role in restraining the reinforced concrete columns,limiting the generation and development of cracks,improving the ultimate failure state of reinforced concrete columns,and greatly improving the energy dissipation capacity and deformation capacity of reinforced concrete columns.On the basis of the seismic test,the numerical simulation is carried out by the finite element software ABAQUS.The analysis results show that the ductility and energy dissipation performance of reinforced concrete columns can be improved by increasing the amount of basalt fiber cloth,but when the amount of BFRP reaches a certain amount,the ductility and energy consumption of columns increase little.Under the same confining strength ratio of FRP,the deformation capacity and the energy dissipation performance of columns strengthened with BFRP is slightly higher than columns strengthened with CFRP.Finally,combined with the existing CFRP reinforced column specification of the stirrup ratio conversion formula,the stirrup ratio gives suggestions on the conversion of BFRP,and the fitting formula of displacement ductility coefficient is proposed,to verify the reliability of the effective constraint parameters of BFRP proposed in this paper.