Collapse Risk of Self-Centering Moment Resisting Frames with Viscous Dampers in Near-Fault Regions

Abstract

This paper evaluates the seismic collapse capacity of self-centering momentresisting frames (SC-MRFs) with viscous dampers located in near-fault regions. For this purpose, a prototype steel building was designed using different seismicresistant frames, i.e.: conventional steel moment-resisting frames (MRFs); MRFs with viscous dampers; SC-MRFs; and SC-MRFs with viscous dampers. The frames are modeled in OpenSees where material and geometrical nonlinearities are taken into account as well as cyclic strength and stiffness degradation. A database of 91 near-fault, pulse-like ground motions with varying pulse periods is employed for the nonlinear dynamic analyses. Collapse capacity of the frames is evaluated through incremental dynamic analysis (IDA). The results of the IDA are combined with probabilistic seismic hazard analysis models that account for near-fault directivity to assess collapse risk of the structures. Results show that the predicted collapse capacity is affected by the pulse period of the near-fault ground motions and highlight that SC-MRFs have superior collapse resistance. Finally, it is shown that the use of viscous dampers significantly improves collapse resistance of all types of frames examined herein.

Enhancing the performance of moment frames using a dumbbell-shaped rocking shear wall with additional devices

“…Collapse risk of self-centering systems in moment-resistant frames as well as the probability of exceeding the inter-story drifts were other components that were covered by researchers. By conducting different incremental dynamic analyses (IDA) in near-eld regions, it was observed that the probability of collapsing and exceeding the inter-story threshold, signi cantly decreases when using post-tensioning elements and viscous dampers [8][9][10].…”