CAREER: Performance-Based Fire Design for Cold-Formed Steel Structures

This Faculty Early Career Development (CAREER) award will derive an advanced science-based framework for assessing the fire performance of cold-formed steel structures. This framework will enable more accurate modeling of the effect of fire on cold-formed steel structures that will support improved design methods for advancing national prosperity and welfare through better safety, resource efficiency, and resilience against fire. Lightweight cold-formed steel structural systems, with high strength-to-weight ratio and rapid construction speed, are widely used in nonresidential construction in the United States. Cold-formed steel structures are traditionally protected from fire based on prescriptive provisions derived from standardized testing. However, the reliance on prescriptive provisions is costly and impedes innovation toward more sustainable and affordable buildings. This research project will develop experimental and computational capabilities for the fire analysis of cold-formed steel structures that will advance understanding of the fundamental relationship between the thermal exposure and the stability and strength of these thin-walled members, to enable better structural fire designs. The research will be complemented by an educational and outreach program to engage a broad audience on the role of structural fire engineers in building resilient communities against extreme hazards. The program will include curriculum development, outreach activities, and educational videos developed in collaboration with the Maryland Institute College of Art. Data generated from this project will be made publicly available in the National Science Foundation-supported Natural Hazards Engineering Research Infrastructure Data Depot (https://www.DesignSafe-CI.org). The specific goal of the research is to enable performance-based fire design for cold-formed steel structures by developing the capability to quantify the fire behavior of the thin-walled framing members. This behavior is largely governed by the interaction between buckling failure modes and elevated temperatures. Thus, this project will include: (i) testing of cold-formed steel studs and joists using an innovative experimental method allowing a range of transient high temperature conditions, (ii) development of thermal-mechanical computational modeling strategies and creation of high-fidelity numerical benchmarks, and (iii) development of analysis-based methods for assessing the fire performance of cold-formed steel structures. The provided data and methods will answer fundamental questions about the complex fire-thermal-structural interaction in these thin-walled members. The research thus has the potential to improve understanding of the mechanics of stability-critical structures in fire and advance simulation capability for cold-formed steel structures under physically based design fires. Beyond cold-formed steel structures, the research will create a leap toward integration of structural fire within the design procedure alongside other loading cases, which supports consistent performance-based and risk-informed design, structural optimization, and multi-hazard resilience assessment. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.