Fire Hazard Analysis and Fire Resistance Evaluation of Historic Timber Buildings Based on Multiple Fire Scenarios

To assess the fire hazards and fire resistance of historic timber buildings, this article proposes a multiple fire scenarios-based fire hazard analysis methodology. Based on the fire risk identification, multiple fire scenarios were constructed. An overall finite element model (FEM) of a historic timber structure under fire exposure in villages and towns in Southwest China was established through the FDS-ABAQUS coupling simulation method and also validated using the fire test results. The fire spread and fire resistance of the structure were analyzed, the temperature variation laws with the time and the failure timeline of the structure were evaluated. Based on the validated FDS-ABAQUS coupling FEM, the influence of the rotational stiffness’s degradation of the mortise and tenon joints on the failure mode of the structure was analyzed. Furthermore, the FE and fire hazard analyses of historic timber structures under various fire scenarios were conducted. The smoke production, visibility levels, carbon monoxide concentration, and temperature distribution during the fire spread were obtained, the safety margin for personnel evacuation was analyzed, the measures and suggestions to reduce the risk of personnel evacuation were proposed. It is found that the FDS-ABAQUS coupling simulations agreed with the fire test results.