Building layout assessment on fire evacuation efficiency by integrating graph theory and virtual reality

The building layout design significantly impacts the fire evacuation process. Existing research focused on evaluating potential evacuation routes and investigating evacuation behaviour with different guidance systems. However, these studies have overlooked the effect of building layout design on visual attention and evacuation behaviour during fire evacuation. Therefore, this paper proposed a methodology to evaluate the building floor plans and evacuation routes by integrating Graph Theory (GT) and Virtual Reality (VR) technology. Building layouts and evacuation routes were represented as graphs and subgraphs, enabling a numerical evaluation of the efficiency of evacuation routes. To further investigate occupants’ attention allocation and evacuation behaviour during the wayfinding process, an eye-tracking function was developed and embedded in a VR platform. Moreover, evacuation behaviours and corresponding time were identified and assigned to the features of edges in the subgraphs, based on which the impact of spatial design on evacuation behaviour was analysed. The findings highlighted the significant impact of route characteristics and signage visibility on attention allocation and evacuation behaviour. Following that, recommendations were provided to building designers to improve fire evacuation efficiency. This study provides emergency behaviour observations and offers a comprehensive evaluation of building layout design, contributing to supporting designers in building design assessment in terms of fire evacuation efficiency.