Research On People’s Evacuation Behavior Rules And Velocity Models At The Crowd Intersections In Teaching Buildings Of Secondary Schools

In teaching buildings, main evacuees are students who have the characteristics of young age, strong mobile capacity and low self-protection awareness which may lead to the regularity and characters differ to those general building evacuation experiments. Considering the limitations of evacuation models and softwares and the complexity of multi-storey teaching buildings at present, the behavior characters and characteristic parameters of the people in teaching building evacuations which are gained by organizing relevant experiments can provide scientific basis and data support for evacuation simulations and building performance-based designs and guarantee efficient evacuations in building stairs. Therefore, the statistical study of evacuation experiments in teaching buildings is very significant.This article mainly aims at the domestic data shortage of actual fire evacuation drill in existing teaching buildings, based on the summary of domestic and international relevant research results, the real data of evacuation drills in the teaching building of Wu Zhongliang middle school has been recorded and clarified, the behavior characters and characteristic parameters of evacuees in different regions of building have been studied, and basically have the following findings:(1) In the evacuation, the speed of people in different regions is accord with the normal distribution, the evacuation speed on the corridor ranges from 0.4 to 4.3 m/s, and the average speed is 1.88 m/s; the evacuation speed on the stairs ranges from 0.4 to 1.0 m/s, and the average speed is 0.70 m/s; the evacuation speed at the stream crossed area ranges from 0.1 to 0.9 m/s, and the average speed is 0.34 m/s. The speed of the stream crossed area is the slowest, followed by the stair section. Comparing with other areas, congestion at the stream crossed area lasts for pretty long time.(2) The evacuees’density distribution on the corridor is mainly between 0.3 to 0.8 per/m2. the maximum density is 1.32 per/m2, the average density is 0.58 per/m2; The evacuees’density on the stairs ranges from 2.0 to 4.8 per/m2, the average density is 4.2 per/m2:In the process of the whole evacuation. Traffic interchange of the density distribution in the process of the whole evacuation, the evacuees’density distribution is mainly between 2.5 to 4.1 per/m2, the maximum density is 5.1 per/m2, the average density is 3.2 per/m2. It can be concluded that the maximum density is discovered in the stair segment, followed by the stream crossed area, the density on corridor is small, and in the process of evacuation, the density at the stream crossed area and stairs are relatively stable.(3) The relationship between speed and density at the stream crossed area is that when D<0.54 per/m2, S=0.76, when D>0.54 per/m2, S=1.402-0.367D; The relationship between speed and density on the corridor is that when D<O.54 per/m2, S=2.71, when D>0.54 per/m2, S=3.259-1.887D; The relationship between speed and density on the stairs is that when D<1.0 per/m2, S=0.79, when D>1.0 per/m2, S=0.825-0.825D. In general, speed and density follow the law of speed decreasing with the increasing of density. But it differs to the experience formula of speed and density which is from American engineers handbook.(4) The competitive relationship of stream getting into the next stair relates to the number of different streams and the order of getting into the stairs. The stream which enters the stairwell previously is more dense and well-organized, and is not easy for other streams to damage its original structure. More streams, more pressure produces by the crowd, and under the pressure, people from different directions alternantly get into the stairwell, finally reach a balance. Previously entering the stairwell and the stream of more people all have some advantages in the competition.(5) Queuing phenomenon exists at the interchange of stair aisles, and general forms a fan-shaped structure; while the small groups phenomenon at the interchange of stair aisles often reduces the evacuation speed behind someone.