EXPERIMENTAL INVESTIGATION ON SEISMIC BEHAVIOR OF PVA FIBER REINFORCED CONCRETE COLUMNS WITH HIGH AXIAL COMPRESSION RATIOS

In order to improve the seismic performance of reinforced concrete columns under high axial compression ratios, replacing ordinary concrete with PVA fiber reinforced concrete is an optional means. Six reinforced concrete column specimens with the shear span ratio of 4 were subjected to quasi-static loading to investigate the seismic behavior of PVA fiber reinforced concrete columns. Four of the specimens are PVA fiber reinforced concrete columns, and the other two specimens are ordinary concrete columns for comparison. The hysteretic behavior, backbone curves, ductility and energy dissipation capacity were investigated under horizontal cyclic loads with a constant axial load for various fiber contents and axial compression ratios. Experimental results show that under high axial compression ratios, the cracks of the PVA fiber reinforced concrete columns develop slowly when they are damaged gradually. The bridging of the fibers effectively inhibits the development of cracks. The failure mode of PVA fiber reinforced concrete columns is ductile. The ultimate drift ratios of the PVA fiber reinforced concrete columns are approximately 1.47 to 1.53 times those of the ordinary concrete columns, indicating that the PVA fiber-reinforced concrete columns have good plastic deformation capacity and damage tolerance. The ratios of energy dissipation of the PVA fiber reinforced concrete columns are 1.82 to 1.95 times those of the ordinary concrete columns, indicating that the PVA fiber reinforced concrete columns have better energy dissipation capacity and seismic performance.