FINITE ELEMENT ANALYSIS OF SEISMIC BEHAVIOR OF PRELOAD -DAMAGED RC ROUND COLUMNS STRENGTHENED WITH HPFL

Based on the results of an experimental study on the seismic performance of 4 full-scale concrete columns reinforced with high performance ferrocement laminates (HPFL) under constant axial forces and cyclic horizontal loads, the numerical simulation analysis of the specimens is carried out. The performance characteristics of the seismic capacity, ductility, stiffness and energy dissipation capacity of the reinforced columns are further studied. At the same time, a method for strengthening RC columns with seismic damage under loading and a simplified calculation method for flexural bearing capacity of such structures are also proposed. Based on this, using reinforcement method and finite element analysis methods proposed, the main factors affecting the seismic performance of RC columns with seismic damage under loading are studied, including axial compression ratio, shear span ratio, transverse mesh reinforcement ratio and reinforcement form. The research shows that: the finite element simulation values, theoretical values and experimental values are in a good agreement. After the HPFL reinforcement, the bearing capacity, ductility and energy consumption capacity of the components are significantly improved, and the degradation rate of stiffness is significantly reduced. After the longitudinal reinforcement of the reinforcement layer is anchored into the base, the improvement of the seismic performance is more superior. With the increase of the axial compression ratio, the bearing capacity is greatly increased, and the ductility is insufficient. As the shear-span ratio increases, the bearing capacity and ductility of the specimens decrease. With the increase of load level difference, the later deformation capacity is obviously weaker. Compared with the ring reinforcement, the spiral reinforcement has the same initial stiffness, the former has better ductility and the latter has higher bearing capacity.