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

Abstract

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 traditional energy dissipation devices is the lack of self-centering capabilities. This results to significant residual deformation, which can significantly affect the building resilience. Failing to eliminate the residual deformation can lead to prolong downtime and significant financial losses. In this paper, a novel damper named self-centering conical friction damper (SCFD) is proposed. SCFD utilizes conical surfaces and posttensioning 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 paper, detailed mechanical behavior for the SCFD is presented. The hysteresis behavior was verified through the experimental tests. The result shows that the proposed theoretical equations can predict the hysteresis response of the SCFD well. Using the derived equations, detailed parameter study including the influences of pretension forces, effective stiffness of posttension tendons, slope angle, and friction coefficients have been investigated. Results show that the hysteresis behavior can be achieved using different combinations of the slope angle, Pretension (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.