Large-scale multi-directional real-time hybrid simulations (RTHS) are used to assess the maximum considered earthquake (MCE) seismic performance of a 40-story steel building equipped with supplemental nonlinear viscous dampers. These dampers are placed between outrigger trusses and the perimeter columns of a building that was part of the inventory for the California Tall Building Initiative (TBI) PEER study. The analytical substructure for the RTHS consists of a 3-D nonlinear model of the building while the experimental substructure consists of a full scale nonlinear viscous damper. Other dampers in the structure are analytically modelled using an online explicit model updating scheme where the physical damper is used to obtain the parameters of the analytical damper models during the RTHS. The displacement, residual drift, and ductility demand are found to be reduced by adding the dampers to the outrigger, but only in the direction of the plane of the outriggers. Higher modes, including torsional modes, contribute to the 3-D seismic response.
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Online explicit model updating of nonlinear viscous dampers for real time hybrid simulation
The system under investigation is a 2-story reinforced concrete building. Nonlinear viscous dampers were placed at the 1st and 2nd stories. The building was subjected to the maximum considered earthquake hazard levels. The outcome of the tests is to assess a newly developed explicit non-iterative formulation for the nonlinear viscous damper model and the ability of the unscented Kalman filter to identify and update the damper parameters in order to improve the model’s prediction of the damper force. The data collected from the tests can be reused by replaying the real-time hybrid simulation offline, where all of the response quantities of the building can be retrieved.
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- Award ID(s):
- 2037771
- NSF-PAR ID:
- 10435926
- Publisher / Repository:
- Designsafe-CI
- Date Published:
- Subject(s) / Keyword(s):
- ["Two Story Reinforced Concrete Building","RTMD IT Simulation Infrastructure","2D planar finite element model","Nonlinear Viscous Damper","Online Explicit Model Updating","Experimental Report - Online Explicit Model Updating"]
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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