Please wait a minute...
Chin. Phys. B, 2017, Vol. 26(10): 104501    DOI: 10.1088/1674-1056/26/10/104501
ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS Prev   Next  

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
Abstract  

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.

Keywords:  crowd flow      discrete element method (DEM)      contact force      force localization  
Received:  26 March 2017      Revised:  04 July 2017      Accepted manuscript online: 
PACS:  45.70.Mg (Granular flow: mixing, segregation and stratification)  
  05.65.+b (Self-organized systems)  
  07.05.Tp (Computer modeling and simulation)  
Fund: 

Project supported by the National Natural Science Foundation of China (Grant No. 71473207) and China Fundamental Research Funds for Central Universities (Grant No. 2682016cx082).

Corresponding Authors:  Peng Lin     E-mail:  drag76@163.com

Cite this article: 

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) A numerical study of contact force in competitive evacuation 2017 Chin. Phys. B 26 104501

[1] Hughes R L 2002 Trans. Res. Part B 226 507
[2] Quarantelli E L 1957 Sociology and Social Research 41 187
[3] Lachapelle A and Wolfram M T 2011 Trans. Res. Part B 45 1572
[4] Dogbe C 2012 J. Math. Anal. Appl. 387 512
[5] Zhang L, Yue H, Li M, Wang S and Mi X Y 2015 Acta Phys. Sin. 64 060505(in Chinese)
[6] Helbing D, Farkas I and Vicsek T 2000 Nature 407 487
[7] Helbing D and Molnár P 1995 Phys. Rev. E 51 4282
[8] Helbing D, Farkas I and Vicsek T 2000 Phys. Rev. Lett. 84 1240
[9] Johansson A and Helbing D 2010 Pedestrian and Evacuation Dynamics pp. 203-214
[10] Johansson A Helbing D and Shukla P K 2008 Adv. Complex Systems 10 271
[11] Chraibi M, Seyfried A and Schadschneider A 2010 Phys. Rev. E 82 046111
[12] Yu W J, Chen R, Dong L Y and Dai S Q 2005 Phys. Rev. E 72 026112
[13] Wang L, Zheng J H, Zhang X S, Zhang J L, Wang Q Z and Zhang Q 2016 Chin. Phys. B 25 118901
[14] Guo F, Li X L, Kuang H, Bai Y and Zhou H G 2016 Physica A 462 630
[15] Tang T Q, Shao Y X and Chen L 2017 Physica A 467 157
[16] Fruin J J 1993 First International Conference on Engineering for Crowd Safety (Lodon)
[17] Keating J P 1982 Fire J. 76 57
[18] Lee R S C and Hughes R L 2007 Math. Comput. Simul. 74 29
[19] Hirshfeld D, Radzyner Y and Rapaort D C 1997 Phys. Rev. E 56 4404
[20] Lin P, Lo S M and Yuen K K 2007 Fire Safety J. 42 377
[21] Pérez G 2008 Pramana 70 989
[22] Adams G G and Nosonovsky M 2000 Tribology International 33 431
[23] Lin P, Ma J and Lo S M 2016 Chin. Phys. B 25 034501
[24] Lin P, Ma J, Liu TY, Ran T, Si Y L and Li T 2016 Physica A 452 156
[25] Lin P, Ma J, Liu TY, Ran T, Si Y L Wu F Y and Wang G Y 2017 Physica A 482 228
[1] Discrete state space method and modal extension method based impact sound synthesis model
Xu-Hua Tian(田旭华), Ke-An Chen(陈克安), Yan-Ni Zhang(张燕妮), Han Li(李晗), Jian Xu(胥健). Chin. Phys. B, 2018, 27(11): 114302.
[2] Relationship between the real contact area and contact force in pre-sliding regime
Baojiang Song(宋保江), Shaoze Yan(阎绍泽). Chin. Phys. B, 2017, 26(7): 074601.
[3] Discrete element crowd model for pedestrian evacuation through an exit
Peng Lin(林鹏), Jian Ma(马剑), Siuming Lo(卢兆明). Chin. Phys. B, 2016, 25(3): 034501.
No Suggested Reading articles found!