Measurement of Structural Performance in Fire

Summary

This project encompasses real-scale experiments to provide technical data to advance the design of structures under realistic fire conditions, validate physics-based computational models to predict the performance of structures exposed to fire, and evaluate new metrology techniques to assess structural response during a fire.

Description

Objective
To conduct large-scale fire experiments that provide the data needed to support the development of validated computational tools for the cost-effective engineering design of fire resistant structures.

Technical Idea
The collapse of the World Trade Center buildings in 2001 revealed the need for a better understanding of the influence of fire on the integrity of modern buildings and structures. Innovation in design and materials for structural fire resistance is accelerated in this project by conducting experiments that support the engineering-based transformation from the current prescriptive approach of building design to performance-based methods. The nearly century-old, prescriptive testing standard for the fire endurance rating of structural components stifles industry innovation and may raise construction costs of non-residential structures. The prescriptive standard fire test method provides little insight into the performance of the structure as a system during real building fires, which can be vastly different from the prescribed standard fire.

NIST’s National Fire Research Laboratory (NFRL) provides the unique capability to measure the performance of real-scale structural systems to simulate real-fire conditions. Data resulting from experiments conducted in the NFRL clarify the fire behavior of structures and validate computational models that predict the system-level fire performance of structures.

Additionally, large scale fire experiments conducted as part of this project provide data appearing in the NIST Fire Calorimetry Database (FCD) for use by practicing Fire Protection Engineers.

Research Plan
This work focuses on developing and testing the performance of structural systems under fire and mechanical loads. It includes conducting experiments to simulate real-world conditions, such as testing composite floor systems and cold-formed steel structures experiencing realistic fire exposures. Key tasks involve creating repeatable fire conditions, conducting detailed experiments to measure structural behavior, and developing standardized testing protocols to ensure consistency across different studies. The project aims to enable performance based engineering design of structures by understanding how they perform under fire conditions, as well as to improve the resilience of buildings, and reduce construction costs. 

Major Accomplishments

• Using the unique capabilities of the NFRL, NIST researchers have gathered data on important new building materials and structures exposed to real fires.
• Experiments that have helped us understand how fire weakens structures and causes them to fail, leading to recommendations on how to make buildings safer during fires.
• Results from the experiments have promoted U.S. innovation and industrial competitiveness, advancing changes to building codes in North America and enabling cost-effective fire protection engineering design.