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Abstract This study investigates the experimental response of a hybrid shape memory alloy (SMA) cable-friction damping device with a specific focus on the failure behavior and reparability of the damper when tested at extreme deformations. The superelastic friction damper (SFD) is a hybrid seismic protection device that combines the high tensile strength and re-centering capability of superelastic SMA cables with stable, repeatable energy dissipation of a friction-based damping system. In this paper, the fabrication of a prototype damper and its experimental testing are discussed. The response of the SFD’s friction and self-centering mechanisms were separately evaluated considering design level deformations, cyclic loading, and large deformations up to failure. The performance of the device after the repair of failed components was also investigated. Findings from the study show that the SFD reached failure at a deformation level that exceeded the design displacement by a factor of 2.2. The force capacity of the SFD at the failure stage was 46% higher than the maximum force at the design deformations. After replacing the failed SMA cables, the damper’s mechanical response was identical to the pre-failure response, illustrating the device’s ability to be restored without hindering performance.
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A hybrid self-centering seismic damper: Finite element modeling and parametric analysis
This study presents a finite element model for a hybrid self-centering damper considering the rate and temperature effects and explores the effects of different design parameters on the damper response. The damper, called as superelastic friction damper (SFD), consists of superelastic shape memory alloy (SMA) cables and a frictional energy dissipation mechanism. The experimental response of the SMA cables, frictional unit and overall damper at different loading frequencies and temperature are used to develop numerical model of the damper. Once a validated numerical model is obtained, parametric studies are carried out to evaluate force-displacement response of the damper when the design parameters are altered. The effects of damper design parameters on the equivalent stiffness, dissipated energy, equivalent viscous damping and self-centering capabilities of the damper are analyzed. Based on the findings, the recommendations for the design of the damper are presented.
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- PAR ID:
- 10486422
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- Journal of Intelligent Material Systems and Structures
- Volume:
- 35
- Issue:
- 4
- ISSN:
- 1045-389X
- Format(s):
- Medium: X Size: p. 440-457
- Size(s):
- p. 440-457
- Sponsoring Org:
- National Science Foundation
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