Experimental Investigation of H-beam to Recycled Aggregate Concrete Column Edge Connections under Cyclic Loading

Abstract

Abstract This paper aims to investigate the cyclic performance of the connections between the recycled aggregate concrete (RAC) column and steel H-beam. In this connection system, the steel beam is welded to the end plate to form an integral unit, which is bolted to the column. The differences in seismic performance between the novel casing-type one-side bolted end-plate connection and the conventional all-welded joint with external diaphragm and top-seat angle connection were investigated. Three types of joints with different connection details were designed and fabricated at a reduced scale of 1:2, following the principle of strong columns and weak beams. The low cyclic lateral loading test was performed by beam-end loading to observe the loading process and failure morphology of the joint model. The load-beam end displacement hysteresis curve and the skeleton curve were obtained to analyze the joint load eigenvalues, ductility, energy dissipation, and stiffness degradation. The experimental results showed that all three specimens exhibited beam-end failure and demonstrated good ductility. Furthermore, a finite element model was established. The effects of axial compression ratio, steel tube width-to-thickness ratio, outer tube, and end-plate thickness on the bearing performance of the outer tube one-side bolted end-plate joint under lateral loading were analyzed. It was found that the bearing capacity and stiffness of the specimens increased with increasing steel tube width-to-thickness ratio, outer tube thickness, and end-plate thickness. Changes in the axial compression ratio had little effect on the bearing capacity and stiffness of the specimens.