中国物理B ›› 2017, Vol. 26 ›› Issue (10): 104501-104501.doi: 10.1088/1674-1056/26/10/104501
• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇 下一篇
A numerical study of contact force in competitive evacuation
Peng Lin(林鹏), Jian Ma(马剑), You-Ling Si(司有亮), Fan-Yu Wu(吴凡雨), Guo-Yuan Wang(王国元), Jian-Yu Wang(王建宇)
- 1. Department of Fire Safety Engineering, Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 610031, China;
2. School of Transportation and Logistics, Southwest Jiaotong University, Chengdu 610031, China
A numerical study of contact force in competitive evacuation
Peng Lin(林鹏)1, Jian Ma(马剑)2, You-Ling Si(司有亮)1, Fan-Yu Wu(吴凡雨)1, Guo-Yuan Wang(王国元)1, Jian-Yu Wang(王建宇)2
- 1. Department of Fire Safety Engineering, Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 610031, China;
2. School of Transportation and Logistics, Southwest Jiaotong University, Chengdu 610031, China
摘要：
Crowd force by the pushing or crushing of people has resulted in a number of accidents in recent decades. The aftermath investigations have shown that the physical interaction of a highly competitive crowd could produce dangerous pressure up to 4500 N/m, which leads to compressive asphyxia or even death. In this paper, a numerical model based on discrete element method (DEM) as referenced from granular flow was proposed to model the evacuation process of a group of highly competitive people, in which the movement of people follows Newton's second law and the body deformation due to compression follows Hertz contact model. The study shows that the clogs occur periodically and flow rate fluctuates greatly if all people strive to pass through a narrow exit at high enough desired velocity. Two types of contact forces acting on people are studied. The first one, i.e., vector contact force, accounts for the movement of the people following Newton's second law. The second one, i.e., scale contact force, accounts for the physical deformation of the human body following the contact law. Simulation shows that the forces chain in crowd flow is turbulent and fragile. A few narrow zones with intense forces are observed in the force field, which is similar to the strain localization observed in granular flow. The force acting on a person could be as high as 4500 N due to force localization, which may be the root cause of compressive asphyxia of people in many crowd incidents.
中图分类号: (Granular flow: mixing, segregation and stratification)
- 45.70.Mg