Publications Details

Intermediate-scale fire performance of composite panels under varying loads

Brown, Alexander B.; Dodd, Amanda B.

New aircraft are being designed with increasing quantities of composite materials used in their construction. Different from the more traditional metals, composites have a higher propensity to burn. This presents a challenge to transportation safety analyses, as the aircraft structure now represents an additional fuel source involved in the fire scenario. Most of the historical fire testing of composite materials is aimed at studying decomposition, flammability or yield strength under fire conditions. The majority of this testing has been performed on a small-scale. Heterogeneous reactions are often length-scale dependent, and this is thought to be particularly true for composites which exhibit significant microscopic dynamics that can affect macro-scale behavior. A series of discovery tests has been designed to evaluate composite materials under various structural loading conditions with a consistent applied thermal boundary condition. Mass-loss, heat flux, and temperature response have been measured throughout the experiment. Several panels have been tested, including simple composite panels, and sandwich panels. A major objective of the testing was to understand the importance of the structural loading on a composite material during exposure to firelike conditions. During flaming combustion at early times, there are features of the panel decomposition that are unique to the type of structural loading imposed on the panels. At load levels tested, fiber reaction rates at later times appear to be independent of the structural loading.