Abstract: The leadership parameter of small group was introduced into the traditional social force model to modify movement direction and speed of small group members in the evacuation process. The Agent model was established based on modified social force model and the calculation was carried out by Anylogic. Then evacuation time of small group members in conditions of different small group size, the proportion of small group members in whole occupants and the meeting place were statistically analyzed. The influence of the above small group behavior parameters on evacuation time was obtained. The results indicated that larger small group size, higher proportion of small group members in whole occupants and closer distance from the meeting place to the middle of the room can all result in longer evacuation time.

Key words: modified social force model, Agent model, small group behavior, evacuation time