Seismic Damage Assessment of a Beam-to-Column Connection with Blind Bolts and T-stubs
With the increasing application of prefabricated steel structures in the construction engineering field,blind bolted connection is gradually favored by the industry as an efficient and convenient connection method.A new type of prefabricated steel frame structure is formed by connecting H-section beams and hollow section columns with T-stub connectors and blind bolted connection technology.As the core of the entire frame system,the seismic performance of beam-column joints is crucial to the overall structure.To evaluate the damage of beam-column joints which connected with blind bolts and T-stubs during earthquake,quasi-static tests on four beam-column joints with different stiffness of T-stub were carried out.The failure mode,hysteretic behavior and initial rotation stiffness of beam-column joints connected by blind bolts and T-stubs were obtained by experimental research and the effects of the different stiffness of T-stub on the failure mode,bending moment bearing capacity and stiffness degradation of beam-column joints were analyzed.The Park-Ang damage index model,which considering the cumulative damage correction of residual deformation was used to study the damage evolution law of the joints in the test.The results show that the seismic damage model proposed in this paper can better reflect the damage evolution process and damage degree of the beam-column joints with blind bolts and T-stubs,which provides a theoretical basis and practical experience for the optimal design and safety assessment of such beam-column joints.