skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Attention:

The DOI auto-population feature in the Public Access Repository (PAR) will be unavailable from 4:00 PM ET on Tuesday, July 8 until 4:00 PM ET on Wednesday, July 9 due to scheduled maintenance. We apologize for the inconvenience caused.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


  • NSF Public Access
  • Search Results
  • Earthquake and Post-earthquake Fire Testing of a Mid-rise Cold-formed Steel Framed Building. I: Building Response and Physical Damage
Title: Earthquake and Post-earthquake Fire Testing of a Mid-rise Cold-formed Steel Framed Building. I: Building Response and Physical Damage
To advance understanding of the multihazard performance of midrise cold-formed steel (CFS) construction, a unique multidisciplinary experimental program was conducted on the Large High-Performance Outdoor Shake Table (LHPOST) at the University of California, San Diego (UCSD). The centerpiece of this project involved earthquake and live fire testing of a full-scale 6-story CFS wall braced building. Initially, the building was subjected to seven earthquake tests of increasing motion intensity, sequentially targeting service, design, and maximum credible earthquake (MCE) demands. Subsequently, live fire tests were conducted on the earthquake-damaged building at two select floors. Finally, for the first time, the test building was subjected to two postfire earthquake tests, including a low-amplitude aftershock and an extreme near-fault target MCE-scaled motion. In addition, low-amplitude white noise and ambient vibration data were collected during construction and seismic testing phases to support identification of the dynamic state of the building system. This paper offers an overview of this unique multihazard test program and presents the system-level structural responses and physical damage features of the test building throughout the earthquake-fire-earthquake test phases, whereas the component-level seismic behavior of the shear walls and seismic design implications of CFS-framed building systems are discussed in a companion paper.  more » « less
Award ID(s):
1663569
PAR ID:
10341546
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Journal of structural engineering
ISSN:
0733-9445
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ; ; ; ; (, 2025 Proceedings of the Structural Stability Research Council Annual Stability Conference)
    The objective of this paper is to investigate the post-earthquake thermal-mechanical response of cold-formed steel (CFS) members. A 10-story cold-formed steel building (CFS-NHERI) will undergo seismic tests, followed by post-earthquake live fire tests. To support the fire test setup, computational models are developed to simulate the impact of varying post-earthquake damage levels on the fire response of the structure. As a panelized system, damage to different finish and nonstructural systems significantly affects the thermal behavior and load-bearing capacity of the CFS components. The computational models integrate the modeling capability in CUFSM and SAFIR for the elastic buckling, heat transfer, and transient structural analysis under fire. A parametric analysis considering different seismic damage levels is conducted to study the buckling and strength behavior of the CFS members under fire-induced nonuniform temperature fields. These pre-test models inform the duration and severity of the fire tests to maintain structural stability while achieving substantial thermal loading on the CFS load-bearing system. They also provide guidance for the sensor layout plan for the fire tests. This study advances methods for fire resilience of thin-walled CFS structures under multi-hazard scenarios. 
    more » « less
  2. ; ; ; ; ; ; ; ; ; ; et al (, Designsafe-CI)
    A test program was designed to answer if it is possible to design and build a tall mass timber building with resilient performance against large earthquakes. Resilient performance was defined as to receive no structural damage under design level earthquake, and only easily repairable damage under maximum considered earthquake. The system under investigation is a full-scale 10-story mass timber building designed and constructed with many innovative systems and details including post-tensioned wood rocking wall lateral systems. Non-structural components on the building were also tested to ensure their damage in all earthquakes are repairable and will not significantly delay the functional recovery of the building after large earthquakes. The tests were conducted using multi-directional ground motion excitations ranging from frequent earthquakes to maximum considered earthquakes. The resultant dataset contains a total of 88 shake table tests and 48 white noise tests conducted on the building at the high-performance outdoor shake table facility in San Diego CA. U.S.A. Data was obtained using over 700 channels of wired sensors installed on the building during the seismic tests, presented in the form of time history of the measured responses. The tall wood building survived all excitations without detectible structural damage. This publication includes detailed documentation on the design and testing of the building, including construction drawing sets. Representative photo and video footage of the test structure during construction and testing are also included. This dataset is useful for researchers and engineers working on mass timber building design and construction in regions of high seismicity. 
    more » « less
  3. ; ; ; ; ; ; (, ATC/SPONSE Fifth International Workshop on the Seismic Performance of Non-Structural Elements (SPONSE))
    During extreme events such as earthquakes, stairs are the primary means of egress in and out of buildings. Therefore, understanding the seismic response of this non-structural system is essential. Past earthquake events have shown that stairs with a flight to landing fixed connection are prone to damage due to the large interstory drift demand they are subjected to. To address this, resilient stair systems with drift-compatible connections have been proposed. These stair systems include stairs with fixed-free connections, sliding-slotted connections, and related drift-compatible detailing. Despite the availability of such details in design practice, they have yet to be implemented into full-scale, multi-floor building test programs. To conduct a system-level experimental study using true-to-field boundary conditions of these stair systems, several stair configurations are planned for integration within the NHERI TallWood 10-story mass timber building test program. The building is currently under construction at the UC San Diego 6-DOF Large High-Performance Outdoor Shake Table (LHPOST6). To facilitate pre-test investigation of the installed stair systems a comprehensive finite element model of stairs with various boundary conditions has been proposed and validated via comparison with experimental data available on like-detailed single-story specimens tested at the University of Nevada, Reno (UNR). The proposed modelling approach was used to develop the finite element model of a single-story, scissor-type, stair system with drift-compatible connections to be implemented in the NHERI TallWood building. This paper provides an overview, and pre-test numerical evaluation of the planned stair testing program within the mass timber shake table testing effort. 
    more » « less
  4. ; (, 2025 Proceedings of the Structural Stability Research Council Annual Stability Conference)
    This paper describes an experimental study on the behavior of load-bearing cold-formed steel (CFS) members under elevated temperatures from fire exposure. A custom-built electrical furnace with six independently controlled heating zones was installed in a loading frame, enabling testing of CFS members under uniform or non-uniform elevated temperatures. The ability to precisely control temperature gradients between the flanges allows testing a single member to failure under thermal conditions representative of a wall assembly exposed to fire on one side, capturing the effect of thermal gradient on the buckling behavior. Steady-state tests on short (18 in.) 600S200- 54 lipped channels in compression were conducted at temperatures up to 600 °C, including tests with uniform temperatures and tests with 100°C gradient between the two flanges. Coupon tests were also conducted to characterize the material properties at elevated temperatures. The members lost about 23% of their strength at 400°C and 66% at 600 °C. For these short specimens under nonuniform heating, with one flange 100°C hotter than the other, the member strength fell between the strengths associated with the temperatures of the hot and cold flanges, with limited asymmetric effect on the local buckling response. This experimental data can support the development of design methods for CFS members in fire, enabling performance-based fire design. 
    more » « less
  5. ; ; ; ; ; ; ; ; ; ; et al (, Frontiers in Built Environment)
    null (Ed.)
    Since its commissioning in 2004, the UC San Diego Large High-Performance Outdoor Shake Table (LHPOST) has enabled the seismic testing of large structural, geostructural and soil-foundation-structural systems, with its ability to accurately reproduce far- and near-field ground motions. Thirty-four (34) landmark projects were conducted on the LHPOST as a national shared-use equipment facility part of the National Science Foundation (NSF) Network for Earthquake Engineering Simulation (NEES) and currently Natural Hazards Engineering Research Infrastructure (NHERI) programs, and an ISO/IEC Standard 17025:2005 accredited facility. The tallest structures ever tested on a shake table were conducted on the LHPOST, free from height restrictions. Experiments using the LHPOST generate essential knowledge that has greatly advanced seismic design practice and response predictive capabilities for structural, geostructural, and non-structural systems, leading to improved earthquake safety in the community overall. Indeed, the ability to test full-size structures has made it possible to physically validate the seismic performance of various systems that previously could only be studied at reduced scale or with computer models. However, the LHPOST's limitation of 1-DOF (uni-directional) input motion prevented the investigation of important aspects of the seismic response of 3-D structural systems. The LHPOST was originally conceived as a six degrees-of-freedom (6-DOF) shake table but built as a single degree-of-freedom (1-DOF) system due to budget limitations. The LHPOST is currently being upgraded to 6-DOF capabilities. The 6-DOF upgraded LHPOST (LHPOST6) will create a unique, large-scale, high-performance, experimental research facility that will enable research for the advancement of the science, technology, and practice in earthquake engineering. Testing of infrastructure at large scale under realistic multi-DOF seismic excitation is essential to fully understand the seismic response behavior of civil infrastructure systems. The upgraded 6-DOF capabilities will enable the development, calibration, and validation of predictive high-fidelity mathematical/computational models, and verifying effective methods for earthquake disaster mitigation and prevention. Research conducted using the LHPOST6 will improve design codes and construction standards and develop accurate decision-making tools necessary to build and maintain sustainable and disaster-resilient communities. Moreover, it will support the advancement of new and innovative materials, manufacturing methods, detailing, earthquake protective systems, seismic retrofit methods, and construction methods. This paper will provide a brief overview of the 1-DOF LHPOST and the impact of some past landmark projects. It will also describe the upgrade to 6-DOF and the new seismic research and testing that the LHPOST6 facility will enable. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email