DUCTILITY ASSESSMENT OF REINFORCED CONCRETE PILE-TO-PILE CAP CONNECTIONS IN APPLICATION

Abstract

Ground motion occurred during moderate seismic event causes pile-to-pile cap connections producing a large curvature demand and a plastic hinge at the pile head. Severity damage along the pile is controlled by limiting the curvature ductility demand in the potential plastic hinge region of the pile. The strength and stiffness of the soil-pile interaction and the equivalent plastic hinge length of the pile directly quantify the curvature ductility demand of fixed pile-to-pile cap connection. A routine that incorporates the limit state analysis based on the kinematic model and the moment-curvature analysis was developed to calculate the displacement ductility factor to the local curvature ductility demand. A fixed-head pile-to-pile cap connection embedded in cohesive and cohesionless soils was studied. The result shows that the first plastic hinges for both soil conditions occur at the interface of fixed-head pile connection. The ductility assessment demonstrates that curvature ductility demands for the fixed-head pile embedded in cohesive soil is higher compared to the pile embedded in cohesionless soil providing a different location of the second plastic hinges.