Numerical Acceptance Criteria for FEMA Performance Levels of Reinforced Concrete Circular Bridge Piers Strengthened with FRP Laminate

One of the drawbacks of using fiber reinforced plastic composite materials (FRP) in rehabilitation of vulnerable RC structures from analytical view point is lack of numerical acceptance criteria to attain desired performance goal. The major parameter to control performance in nonlinear behavior is plastic hinge rotation angle (PHRA) especially for deformation- controlled actions. Confinement is an element of increasing PHRA capacity. The present study shows high performance of FRP in confinement of reinforced concrete compression members. The results of previous investigations show parameters such as FRP thickness to section diameter ratio (aspect ratio), the relative height of FRP and the FRP material characteristic that may have influenced behavior of compression member strengthened with FRP under combine axial-flexural loading. To predict accurate performance of RC concrete columns strength with externally-bonded FRP, there is an urgent need to discover PHRA as an acceptance criteria in a nonlinear static procedure stipulated in ASCE/SEI 41-06 standard (1). For easy use analytical formulation is calibrated to evaluate PHRA as the function of these triple parameters. An attempt has been made to simulate the RC piers strengthen with FRP laminate with a suitable finite element program. The general-purpose FEA software Abaqus ™ (v6.8) (2) has been used to set up the finite element model in three dimensions. Verification of the numerical method has been done by comparing numerical results versus existing experimental tests.