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This paper investigates the effects of near-fault pulse-type ground motions on the structural response of a 3-story steel structure with nonlinear viscous dampers using the real-time hybrid simulation (RTHS) testing method. The real time loop of action and reaction between the experimental and numerical partitions executed in the RTHS enabled the accurate capturing of the velocity pulse effects of pulse-type ground motions. An ensemble of 10 natural pulse-type ground motions at the design basis earthquake (DBE) level is used for the RTHS. The accuracy of RTHS under high velocity loading is demonstrated, and thereby, is a validated method for experimentally investigation of the complicated structural behavior of structures with rate-dependent damping devices. The test results showed that the dampers are essentially effective in earthquake hazard mitigation effects involving pulse-type ground motions. The average peak story drift ratio under the set of pulse-type ground motions is 1.08% radians with a COV value less than 0.3, which indicates that the investigated structure would achieve the ASCE 7-10 seismic performance objective for Occupancy Category III structures under the DBE level pulse-type ground motions.
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This content will become publicly available on August 29, 2026
A study on solitary-wave-structure interaction using hydro real-time hybrid simulation
In seismic regions, structures along the coast may be exposed to earthquake and tsunami loading during their service life. During the 2011 Great East Japan Earthquake, many structures survived the earthquake but failed due to the subsequent tsunami loading. This research aims to generate data about the effects of tsunami waves on coastal structures, however, conventional approaches have limitations when simulating structures interacting with hydrodynamics. Computational methods require experimental validation, but scaled experimental methods may not represent full-scale prototype response because of the unique similitude law governing the hydrodynamics versus the structural dynamics. Real-time hybrid simulation (RTHS) can alleviate the similitude limitations by partitioning the system subjected to structural- and hydrodynamics into physical and numerical sub-assemblies. The sub-assemblies interact through actuators and sensors in real time, which enables the application of individually applied similitude laws to each sub-assembly. Here, physical solitary waves and a very stiff cylindrical physical specimen were coupled with a numerical single degree-of-freedom (SDOF) oscillator via RTHS. In the NHERI Large Wave Flume at Oregon State University, breaking and broken solitary waves excited the physical specimen, whose natural period was then numerically manipulated. Results showed that the effects of wave-structure interaction depend on the duration of the wave loading and natural period of the SDOF system.
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- Award ID(s):
- 2310171
- PAR ID:
- 10632042
- Publisher / Repository:
- 18th World Conference on Earthquake Engineering (18WCEE)
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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