Nonlinear Analysis On Seismic Behavior Of PVA-steel Hybrid Fiber Reinforced Cementitious Composite Column

With the development of material technology,high strength and high performance materials are more and more widely used in construction industry.PVA-steel Hybrid Fiber Reinforced Cementitious Composites(H y FRCC)has the characteristics of quasi-strain-hardening and multi-crack cracking,which can effectively remedy the defects of common concrete such as easy cracking and poor ductility,the ductility and energy dissipation of PVA-steel Hy FRCC columns are obviously improved,so it is of great theoretical significance to study the seismic behavior of PVA-steel Hy FRCC columns.The method of numerical simulation can reflect the seismic performance of the members comprehensively,thus providing sufficient basis and reliable theoretical basis for the experiment and engineering application.Based on the Open SEES platform,this dissertation studies the seismic behavior of PVA-steel Hy FRCC columns in the following aspects:(1)Based on the constitutive models of C oncrete02,Steel02 and Bond-SP01 in Open SEES software,the seismic experiments of ordinary concrete colu mns were simulated.The results showed that the fiber model based on the stiffness method and considering the bond-slip effect between steel bar and concrete ha d better accuracy,and could simulate the“Pinch-shrinkage” effect of RC column hysteretic curve,the energy dissipation capacity of RC columns subjected to cyclic reciprocating loading was accurately reflected,and the simulation results were in good agreement with the experimental results.(2)Based on the Open SEES platform,the improved Concrete02 constitutive model and ECC01 constitutive model were used to simulate the constitutive relationship of PVA-steel Hy FRCC columns and the experimental results were compared.The results showed that,compared with ECC01 constitutive model,the error of the hysteretic curve,peak load capacity,displacement ductility coefficient and equivalent viscous damping coefficient simulated by the improved Concrete02 constitutive model was smaller than that of the experimental value,it was shown that the improved Concrete02 constitutive model was better than the ECC01 constitutive model in the study of seismic behavior of PVA-steel Hy FRCC columns.(3)Based on Open SEES platform,the improved Concrete02 constitutive model was used to study the influence of axial pressure ratio,shear span ratio,reinforcement ratio and stirrup ratio on the seismic performance of PVA-steel Hy FRCC columns.The results showed that with the increase of axial pressure ratio,the stiffness degradation rate of the specimen increases,the energy dissipation performance and ductility gradually decrease.With the increase of the reinforcement ratio,the energy dissipation capacity and ductility of the specimens increased greatly,while the ductility and bearing capacity increased slightly.With the increase of the volume stirrup rate,the energy dissipation capacity and ductility of the specimen increase are small.