LAUSR

The common characteristic of self-centering (SC) post-tensioned (PT) connections is the gap opening and closing at the beam-column interface, which often face the problem of deformation incompatibility with floor system and cause severe damage of floor slab. To address this drawback of PT frame expansion, an innovative friction-damped SC coupled-beams (CBs) that incorporate PT strands to provide a SC capacity along with friction devices (FDs) to dissipate energy is presented. The global mechanics of this system are briefly explained. An individual FD is tested to investigate the wear resistant properties and friction coefficients of friction materials for the energy dissipation system of SC-CBs. Detailed three-dimensional finite element models (FEMs) of a single-story single-bay frame using SC-CBs are developed with consideration of different FDs installation positions. Analytical results indicate that SC-CBs can sustain large lateral deformations without structural damage under cyclic loading. Then, simplified computational models are validated based on the solid models and applied in nonlinear dynamic analysis of a five-story MRFs using SC-CBs. The frame using SC-CBs minimizes the residual drift and displays good energy dissipation capacity under both the design basis and maximum considerable levels of seismic loading.