Seismic Behavior of Post-Tensioned Steel Column Base with Friction Energy Dissipation Devices

This research aims to investigate the seismic behavior of post-tensioned steel column base with friction energy dissipation devices, and study the effects of initial post-tensioned force of strands and energy dissipation devices. The column and foundation is connected by using high-strength strands to provide self-centering behavior, and the energy dissipation devices utilizing friction are to provide hysteretic behavior. Therefore, the column possesses characteristics of self-centering and no residual deformation. A few critical parameters are studied including initial post-tensioned force, area of energy dissipation, and location of friction energy dissipation devices. The behavior of the joint is evaluated in both analytical and experimental studies. The results show that increasing post-tensioned force of the bolts used for friction energy dissipation devices could effectively enlarge the area of energy dissipation. Increasing the initial post-tensioned force of strands can move up the hysteretic loop and ensure self-centering capacity of column. The energy dissipation devices installed at the column flange rather than column web lead to better energy dissipation behavior and more economic. The joint between column and foundation, with friction energy dissipation devices, possesses self-centering, gap opening and closing at the column-to-foundation interface, energy dissipation characteristics, and no residual deformation on column. Moreover, analytical predictions agree well with experimental data.