Abstract:

To achieve rapid post-earthquake restoration of structures, a chevron braced steel frame structure with replaceable energy dissipation joints is proposed with using the design concept of controllable damage and replaceable energy dissipation joints. To explore the seismic performance of the structure and post-earthquake repair performance of structure, quasi-static tests were conducted on a 1/2 scale single story single span substructure specimen and the repaired specimen. The hysteretic curves, skeleton curves, stress curves and ductility of the specimens were studied an compared in the initial and repaired specimen. The results showed that the spindle shaped hysteretic curves is quite plump. The damage of this structure is mainly concentrated on replaceable energy dissipation joints, and the main frame is basically remained in elasticity. After the 0.83% inter-storey drift, the loading is completed. The residual inter-storey drift ratio of the structure is 0.28%, and the mechanical properties of the structure after replacing the energy dissipation joints are similar to original structures. The simplified analytical modes of chevron braced steel frames with replaceable energy dissipation joints was established, the calculation method of the elastic lateral stiffness of the structure was derived based on the deformation coordination relationship and the calculation formula of the bearing capacity of the structure when the double U-shaped metal energy dissipator yields was proposed. The maximum error between the theoretical calculation result of the elastic lateral stiffness of the structure and the experimental result was 3.72%, and the maximum error between the theoretical calculation result and the experimental result when the double U-shaped metal energy dissipator yields was 9.41%.

Key words: replaceable energy dissipation joints, chevron braced steel frame, quasi static test, seismic performance