Coupling of Concrete Walls Using Post-Tensioned Precast Concrete Beams

摘要

This paper describes an analytical investigation on the nonlinear behavior ofrnpost-tensioned precast concrete beams to couple reinforced concrete walls. Differentrnfrom conventional systems that use monolithic cast-in-place reinforced concreterncoupling beams or embedded steel coupling beams, the nonlinear behavior of post-tensionedrnprecast concrete coupling beams is governed by the opening of gaps at thernbeam ends. Steel top and seat angles are used at the beam-to-wall connections tornyield and dissipate energy in the event of a large earthquake. Two types of analyticalrnmodels are developed using the DRAIN-2DX and ABAQUS programs forrnverification of the results and more detailed evaluation of the expected behavior.rnNonlinear reversed cyclic lateral load analyses of four coupling beam subassembliesrnare conducted. The main parameters investigated are the beam depth, the area of thernpost-tensioning steel, and the size of the top and seat angles. The results indicate thatrnpost-tensioned precast concrete coupling beams possess stable behavior through largernrotations, significant self-centering capability due to the post-tensioning force, andrnsignificant energy dissipation provided by the yielding of the top and seat angles.