Decision-Making and Group Behaviors in a Building Evacuation Experiments Considering Occupancy Social Network

In this paper, social network analysis method is applied to verify that daily life social relation is an important factor affecting individual and group behaviors and evacuation efficiency. Evacuation experiments are conducted by carrying out 15 multi-mode collaborative evacuation drills including 6 in 2014 and 9 in 2015.The same group of 30 evacuees from a undergraduate class has been tracked for two years. Social network method is used to study following behavior, leading behavior and decision-making behavior in evacuation experiments. Through the questionnaires before and after all the evacuation drills, by defining the mutual trust degree (MTD) and being followed degree (BFD), the MTD relation matrix on daily life and the BFD relation matrix in evacuation can be constructed. Then normal social relation network graph and following relation network graph in emergency are drawn. Results show that small groups and leaders will be formed automatically during group evacuation, and the leaders in emergency demonstrate some certain stability, which has some relevance with gender and relations in normal situation. When two emergency exits are available during evacuation including stair and elevator, evacuation efficiency is best when the elevator and stair are located at the same side.