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|Massenpanik|-|Mass Panic|–[wissenschaftl|scientific] [en|de]


http://wp.me/P10CD1-dG (shortlink of this page)
http://wp.me/10CD1 (shortlink of this Website)



IN BEARBEITUNG!


PRE Version //originally started to compile this information -> 11th August of 2010



http://www.ethlife.ethz.ch/archive_articles/100727_Massenpanik_Helbing_sch/Pedestrian_Crowd_and_Evacuation_Dynamics_Helbing.pdf

Pedestrian, Crowd and Evacuation Dynamics

DIRK HELBING1,2 , ANDERS JOHANSSON1
1 ETH Zurich, Zurich, Switzerland
2 Institute for Advanced Study, Collegium Budapest,
Budapest, Hungary


#0


The physical interactions in jammed crowds add up
and can cause dangerous pressures up to 4,500 New-
tons per meter [59,70], which can bend steel barriers
or tear down brick walls.

The strength and direction of the forces acting in
large crowds can suddenly change [87], pushing peo-
ple around in an uncontrollable way. This may cause
people to fall.

Escape is slowed down by fallen or injured people
turning into “obstacles”.

People tend to show herding behavior, i. e., to do what
other people do [69,78].

Alternative exits are often overlooked or not efficiently
used in escape situations [69,70].

“At occupancies of about 7 persons per square meter
the crowd becomes almost a fluid mass. Shock waves
can be propagated through the mass, sufficient to . . .
propel them distances of 3 meters or more. . . . People
may be literally lifted out of their shoes, and have cloth-
ing torn off. Intense crowd pressures, exacerbated by
anxiety, make it diffcult to breathe, which may finally
cause compressive asphyxia. The heat and the ther-
mal insulation of surrounding bodies cause some to be
weakened and faint. Access to those who fall is impos-
sible. Removal of those in distress can only be accom-
plished by lifting them up and passing them overhead
to the exterior of the crowd.” (J. Fruin in [88].)




http://www.crowdsafe.com/FruinCauses.pdf

THE CAUSES AND PREVENTION OF CROWD DISASTERS

by
John J. Fruin, Ph.D., P.E.
United States of America

(Originally presented at the First International Conference on Engineering for Crowd Safety
London, England, March 1993. Revised exclusively for crowdsafe.com, January 2002.)



#1


THE VIEW FROM THE CROWD
It is difficult to describe the psychological and physiological pressures within crowds at
maximum density. When crowd density equals the plan area of the human body, individual
control is lost, as one becomes an involuntary part of the mass. At occupancies of about 7
persons per square meter the crowd becomes almost a fluid mass. Shock waves can be
propagated through the mass sufficient to lift people off of their feet and propel them distances
of 3 m (10 ft) or more. People may be literally lifted out of their shoes, and have clothing torn off.
Intense crowd pressures, exacerbated by anxiety, make it difficult to breathe. The heat and
thermal insulation of surrounding bodies cause some to be weakened and faint. Access to those
who fall is impossible. Removal of those in distress can only be accomplished by lifting them up
and passing them overhead to the exterior of the crowd.


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