Fire Damage Assessment of a Loaded Composite Sandwich Structure Subjected to a Fire

A fire damage assessment tool for a composite sandwich structure has been developed by integrating the 1D heat diffusion equation of a composite sandwich panel with a hybrid progressive damage prediction module within the LS-DYNA3D computational framework. The pyrolysis-driven chemical reaction during a fire has been included in the fire model by incorporating temperature and mass-dependent thermal properties. In comparison with a solid laminate, the accumulative effect from the decomposition, gasification, and vaporous migration of the resin and core has a greater impact on the fire response prediction of sandwich structures. To capture the fire-induced degradation of the material, the synergistic interaction between the discrete and continuum damage, and their compounding effects to the final failure, the hybrid discrete and continuum damage models have been applied in conjunction with mechanism-driven failure criteria. Given the fire induced temperature profiles and the time history of mass loss, the degraded thermal-mechanical properties at ply and laminate level are determined via a virtual testing tool. The capability of the developed fire damage assessment tool has been demonstrated via a fire damage characterization of a loaded sandwich beam subjected to a fire. The use of the temperature dependent thermal properties has shown to have a greater impact on the fire response prediction of a sandwich material as compared with a solid composite laminate.