Interface Model to Fire-Thermo-Mechanical Performance-Based Analysis of Structures Under Fire Conditions

This work is dedicated to the development of a computational model to perform an interface for fire thermomechanical performance-based analysis of structures under fire conditions. The proposed analysis procedure links the fire-driven fluid flow model, developed with the code Fire Dynamics Simulator (FDS), and a structural thermomechanical analysis via ANSYS commercial package, including large displacements and material plasticity. The developed interface is capable of processing the results from the fire simulation for accounting properly the heat transfer by convection and radiation between the fire and the exposed surfaces (based on Adiabatic Surface Temperature concept) performing the coupling between those two fields.

In this paper, the proposed methodology is applied to a simple case in order to verify the interface against FDS results. This case demonstrates that the interface can account properly the heat transfer from fires to exposed surfaces. Then, the methodology is used to evaluate the fire-thermomechanical behavior of an H-profile column under a localized fire. At the end of analysis it is possible to obtain the structural behavior under specific fire scenarios. In these applications, both solid and shell elements are used demonstrating that the procedure can be applied to evaluate the global behavior of structures. The achieved results also indicate that the suggested methodology can provide reliable performance-based analyses.