Mechanical Anchorage of Bars with Screw-Type Coupler and Perforated Plates in Precast Concrete Beam-Column Joint

摘要

The purpose of this study is to determine the characteristics of the mechanical anchorage of reinforcing bars with screw-type coupler and perforated plate, so called MAB-COP (Mechanical Anchorage of Bars with screw-type COupler and Perforated plate) in precast concrete beam-column joint. The newly proposed mechanical anchorage; MAB-COP is a kind of headed reinforcement, but not screw-threaded on the reinforcement. The bottom bars of the precast beam are anchored by MAB-COP in beam-column joint. A series of test specimens was prepared to consider the effects of the variables, such as the anchorage length of the reinforcing bar (14d_b, 12d_b, 9d_b), and anchoring method. Pullout tests conforming to the ASTM were carried out to assess the effects of several variables on anchoring strength of bars. Based on the test results, it is concluded that the behavior of the specimen anchored by MAB-COP with the anchorage length of 12d_b, was as good as, or better than that of the specimen anchored with 90-degree standard hook.