Abstract: In order to explore influence of small group behavior on decision-making and movement process of pedestrian evacuation, a series of evacuation experiments in buildings with complex layout were carried out. Participants were divided into 24 groups based on sizes of small group and their familiarity degree with layout, and experiment data of exit selection, evacuation path, evacuation speed and decision-making time of each group were obtained and analyzed. The results show that evacuation speed of small groups is slower than that of individuals, but has no correlation with group size. And groups with better familiarity of building layout demonstrate higher evacuation efficiency. In addition, compared with individuals, small groups take more time in decision-making, and pedestrians tend to choose vertical links such as stairs to continue evacuation when facing multiple evacuation routes.

Key words: small group, evacuation experiment, decision behavior, exit selection, route selection