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Materials

Material systems typically have degraded performance at high temperatures present in fires and other extreme environments.  We conduct research on materials and systems to understand their microstructural response and relate that to macroscopic scale performance to support improving the material design. Example of this include

We have developed simulation techniques that couple computational fluid dynamics (CFD) fire dynamics simulations with thermal predictions and structural analysis to accurately predict the response in the spatially dependent, transient exposure scenarios.  In addition, we have created experimental and computational methods to generate the physical and thermal properties of the materials at elevated temperatures.

Fiber-Reinforced Plastic (FRP)

FRP materials are light-weight, corrosion resistance materials with excellent lifecycle performance; however, their structural performance degrades at lower temperatures than traditional metallic construction materials. 

Our research group has conducted multi-scale experimental investigations to relate the microscopic degradation behavior to the macroscopic failure mechanisms that may occur.  This research has been used to create constitutive models for materials to support simulating material behavior.

Engineered Wood Systems

New wood systems are being developed to provide more green, sustainable tall structures.  Their design is more complex compared with traditional metal and concrete systems since these materials char and burn when exposed to fire.

Our group is performing research to create cost-effective methods to evaluate the material performance in large-scale fire resistance tests to accelerate design development.  In this research, scaling laws have been developed to allow for the test article to be reduced in size by up to 1/10th scale while maintaining the same thermal and structural response as it has in large scale.  

Aluminum

Aluminum construction is commonly used in transportation applications due to its high strength to weight ratio.  When exposed to elevated temperatures, the material microstructure may be altered reducing its strength properties and corrosion resistance.

We have performed research to relate the microstructural evolution of the different 5xxx and 6xxx series aluminum alloys to their elevated temperature and residual post exposure mechanical properties. The research has also explored predicting the occurrence of material burn-through due to fire exposure, which require developing high temperature creep rupture failure models to simulate the behavior.

Firefighting Foams

Liquid fuel (gasoline, diesel, etc.) fires that may occur on commercial airports, roads, rail, or ships are typically suppressed with a firefighting foam, which puts the fire out by covering it with foam blanket that prevent fuel vapors from escaping.  The most effective foams known as Aqueous Film Forming Foams (AFFF) are being banned because they have been found to be environmentally persistent. 

Our group is performing research to understand the microstructural details of the surfactant mixtures used in AFFF foams that make them effective at preventing fuel vapors from penetrating the foam.  With this understanding of the features that make an effective foam, new environmentally friendly foams can be developed.