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A 10-story cold-formed steel (CFS) building, referred to as CFS10, was constructed and tested at the 6-DOF Large High Performance Outdoor Shake Table (LHPOST6) at UC San Diego (NHERI@UC San Diego). This unique building specimen was designed beyond current seismic provisions, notably exceeding the height limit as prescribed in ASCE 7-22 and employing shear wall detailing that is currently not available in the most recent AISI S400-20 design standard. The test specimen was additionally outfitted with a wide range of nonstructural components and systems, designed and installed at various levels of the building, to understand the evolution of damage in a real building system under multi-directional seismic excitation. Limiting damage to nonstructural components plays a key role in maintaining or regaining post- earthquake building functionality. To this end, an essential aspect of the test program is to improve upon the key gaps in the state of knowledge of nonstructural seismic performance and functional recovery of buildings, especially in CFS-framed buildings. This paper presents preliminary observations of damage and functionality correlated with the measured seismic response of select nonstructural systems, namely suspended ceilings, and pressurized fire sprinkler and gas piping systems, focusing on their performance and interactions at the ceiling of Story 10 in the building. Observations related to damage and functionality can inform the development of fragility functions for these nonstructural systems and support improved functional recovery design provisions.
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This content will become publicly available on April 28, 2027
Physical Damage-Measured Response Correlation for Nonstructural Components Tested under Multi-hazard (Earthquake and Fire) Demands in the CFS10 Building
This paper is the second of a set presented within the session: Findings from the CFS10 MultiHazard Test Program. The emphasis within this article is to highlight correlations between physical damage to nonstructural components and systems with measured response during a suite of 18 earthquake tests and two subsequent fire tests. This damage was documented within a 10story cold-formed steel-framed building test specimen outfitted with various nonstructural components, including suspended ceilings, architectural finishes, a resilient stair system, windows and doors, pressurized fire sprinkler and gas piping systems, and roof-mounted mechanical equipment. The test building and multi-hazard protocol are described in the session companion paper. This paper provides test observations correlated with measured engineering demand parameters such as floor acceleration, building inter-story drift or peak local temperature responses and offers related literature emerging from the project. Damage data and functionality checks will support development of fragility functions for these nonstructural systems for use in recoverybased frameworks.
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- Award ID(s):
- 1663569
- PAR ID:
- 10684977
- Publisher / Repository:
- SEI/Structures Congress
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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