Experimental Investigation on Hysteretic Behavior of Staggered Truss-Column Assembled Joints

Abstract:

For the need of engineering application and aseismic design of assembled connection between a staggered steel truss and a column， three kinds of joints were designed with different connection constructions. The hysteretic behavior of chord-web-column truss joints was investigated experimentally under cyclic axial force. It was found that the welded connection between diagonal web member and gusset plate was a weak link， liable to cracking. After the diagonal web member was damaged in the truss joint above， two of the three joints were selected to continue the tests on the hysteretic behavior of chord-column moment frame joints under cyclic bending moment. The performance such as failure feature， load bearing capacity， ductility and energy dissipation as well as influence of connection construction details was analyzed for these joints before and after the diagonal web member was damaged respectively. It is concluded that the truss joints subjected to cyclic axial force has a high loading capacity and initial rigidity， but a general ductility and energy dissipation ability. The chord-column connection configuration has no significant effect on the joint performance. The moment frame joints subjected to cyclic bending moment still has a high bending capacity and energy dissipation ability， but the effect of chord-column connection configuration on the joint performance is significant. In order to resist earthquake action， it is suggested that both the upper and lower flanges of H-section chord member in a staggered steel truss should be connected with the column reliably， which will cause the chord to transfer load to the column by means of bending resistance after the diagonal web member damages and then realize the function of a strong joint.