Mechanism and experimental validation of innovative self-centering conical friction damper

Past earthquakes have shown that traditional structural design relies on the component ductility to dissipate the earthquake energy. This has led to significant damage for the structure. Innovative energy dissipation devices have been developed in the past to dissipate the earthquake energy. However, the big disadvantage of energy dissipation devices is the lack of self-centering feature. Significant residual deformation can have effects on the building resilience. Failing to eliminate the residual deformation can lead to prolong downtime and significant financial losses. In this thesis, a novel damper named self-centering conical friction damper (SCFD) is proposed. SCFD utilizes conical, flat surfaces and post-tensioning tendons to resist the earthquake loads in all directions. The conical surfaces force the SCFD to self-center, making the SCFD highly desired for earthquake applications. In this thesis, detailed mechanical behavior for the SCFD was derived using theoretical equations in this thesis. The hysteresis behavior was verified through the experimental tests. The behavior observed from the test matches well with the theoretical solution Using the derived equations, detailed parameter study including the influences of pretension forces, effective stiffness of post tension tendons, slope angle and friction coefficients have been investigated. Results show the hysteresis behavior can be achieved using different combinations of the slope angle, PT tendons and friction coefficients. Overall, high slope and friction coefficients will lead to highly efficient SCFD with lower demands on the PT tendons. Detailed design approaches have been presented which allows the engineers to design SCDF for different applications. Overall, this thesis shows the SCFD can be used efficiently for application in earthquake engineering with stable energy dissipation and self-centering capabilities.Applied Science, Faculty ofCivil Engineering, Department ofGraduat