Study On The Seismic Performance Of RC Column Strengthened With Polypropylene Fiber Self-compacting Concrete Bonded Steel

Earthquakes cause buildings to collapse around the world every year,which poses a great threat to people’s survival.Therefore,people put forward a series of solutions,such as safety evaluation of buildings with potential safety risks,and reinforcement of buildings that fail to meet the requirements of earthquake resistance.In building reinforcement,column is the focus of attention,it determines the overall stability and security of the building,so column reinforcement is the top priority.On the basis of previous studies,this paper puts forward the idea of strengthening RC columns with polypropylene fiber self-compacting concrete and Angle steel,and uses ABAQUS simulation software to complete the establishment of composite reinforced column model and subsequent analysis and calculation.The objective is to investigate the effect of seven factors on the seismic performance of RC columns,such as the dosage and length of polypropylene fiber,axial compression ratio,Angle edge width,plate spacing,stirrup spacing and self-compacting concrete strength.In order to make the simulation results convincing,this paper compares the relevant data of the verification model with that of the reference specimen,and finds that the change trends of the hysteresis curves and skeleton curves of the two are basically consistent,which indicates that the verification model established in this paper is reasonable and feasible.The simulation results show that in a certain range,the ductility coefficient and energy dissipation coefficient of specimens can be increased by increasing fiber content and fiber length,and the stiffness degradation performance of specimens can be improved.Appropriate reduction of axial compression ratio can improve the ductility and energy dissipation capacity of specimens,which is conducive to the improvement of seismic performance.Increasing the Angle width can improve the energy dissipation coefficient and stiffness of the specimen to a certain extent,but has little effect on the ductility property of the specimen.The ductility and energy dissipation capacity of the specimen can be improved by decreasing the spacing between the plates and stirrup.Increasing the strength of concrete can improve the ductility coefficient and energy dissipation coefficient of the specimen,but can not effectively improve the stiffness degradation property of the specimen.Finally,based on the "truss-arch" model,the formula of shear capacity of ordinary concrete column is established,and the formula of shear capacity of polypropylene fiber and Angle steel system is combined,and finally the formula of shear capacity of composite reinforced column is obtained.