Modeling, simulation and analysis of the evacuation process on stairs in a multi-floor classroom building of a primary school

Few studies have focused on the evacuation of multi-floor classroom buildings in a primary school, a process that differs from evacuations in other buildings. A stair-unit model was proposed to describe the spatial topology of twisting stairwells and to describe the spatial relationship between stairwells and floors. Based on the stair-unit model, a schedule-line model was proposed to calculate evacuation paths in stair-units; a modified algorithm to calculate pedestrian forces were proposed to describe the evacuee movements in stairwells; and a projection strategy was proposed to model the 3-dimensional evacuation process in multi-floor buildings. The simulated processes were compared with a real evacuation drill. The results showed that the simulated process achieved qualitative and quantitative consistencies with the real drill, proving the appropriateness of the proposed models and algorithms. Based on the validation, further simulations were conducted and a few rules for evacuations in stairwells were identified including rules governing the impact of the moment of entering a staircase, the number of students in a class, the stagger strategy, and the layout of grades on different floors on the time in stairwell and the total evacuation duration. The results can be used to mitigate the effects of a fire disaster, and the proposed models and algorithms can also be referenced by evacuation simulation for other multi-floor buildings such as residential buildings.