Tests for aseismic performance of RC rectangular hollow bridge piers constrained with FRP

In order to investigate the aseismic performance of reinforced concrete (RC) rectangular hollow bridge piers constrained with fiber reinforced polymer (FRP), cyclic tests of six RC specimens with aspect ratio 4 under constant axial loads (axial compression ratio is 0.2) and uniaxial bending were conducted here. The aseismic performance parameters including failure characteristic, flexural ductility, dissipated energy and lateral ultimate load capacity were analyzed. The test results indicated that the ductility and dissipated energy of the RC rectangular hollow bridge piers constrained with FRP are improved significantly; the displacement ductility coefficient and the total energy dissipation increase about 65.4% and 25.8%, respectively; the constrained behavior of FRP has little influence on the ultimate lateral force capacity of RC rectangular hollow bridge columns (it increases about 3.0% at most). Based on the test results and Clough model, a simplified hysteretic model considering the strength and stiffness degradation effects of bridge piers constrained with FRP was established and its unloading stiffness and reloading stiffness regression formulae were deduced.