Algorithm And Simulation Of Personnel Evacuation In Buildings

Evacuation for large buildings is an important research direction of emergency evacuation. The purpose of emergency evacuation is to evacuate people from a dangerous area to a safe place in a shortest possible time. When emergency such as fire, poisonous gas and earthquake occurs in a building, evacuation algorithm can guide people evacuate from the building in a shortest possible time. Through modeling and simulation of the evacuation process of evacuees in the building, effects of different evacuation environment and different behavior of evacuees on evacuation process and evacuation time can be researched. In addition, the study of evacuation problems can help in design of the building and optimize the structure of the building for emergency evacuationIn this paper, a study on network based real time evacuation algorithm and cellular automata model based pedestrian flow simulation was made. Then new algorithm and new model were developed from the previous study. The main contents are the following two parts:1. Recursive real time evacuation algorithm based on network modelIn view of the existing algorithm of real-time evacuation based on network model can only be used in single source situation, put forward a new real time evacuation algorithm that can be used in a multi-source and multi-exits situation. The algorithm uses a recursive thought, starting from a single evacuee and obtained an evacuation time and evacuation plan of multi-source multi-exits problem. Then arrange the recursive sequence using the shortest distance in accordance with the evacuees and exit and get an optimized evacuation time and arrangement plan of evacuees. This algorithm overcomes the limitations of fast flow control algorithm which cannot be applied in multiple source situation, and it has a low algorithm complexity than can be used in real-time environment.2. Mixed velocity evacuation flow simulation based on fine cellular automataIn most cellular automata models, evacuees use same movement speed to evacuate from the building. But in real evacuation, evacuees have different speed due to different age and gender. In order to study characteristics of mixed speed evacuation flow based on cellular automata model, a segmentation on the traditional cellular automaton model was made and then two kinds of evacuees with high speed and low speed were added into the new model. In the evacuation process, high-speed and low-speed evacuees can use different evacuation strategy, through the simulation of evacuation flow using different evacuation strategy, the best evacuation strategy for real evacuation was got. Then a simulation of mixed speed evacuation flow in a multi-exits environment using dynamic weight and best evacuation strategy was did. Then an analysis was did to study the evacuation time when the ratio of high and low speed evacuees is different and when the evacuation flow density is different.