PDA

View Full Version : human tolerance to dynamic loading - summary of responses



kmiller46
12-05-2001, 11:34 AM
Dear Colleagues,

Please, find enclosed the summary of responses to my question posted on 29
Nov. 2001. I would like to sincerely thank all who responded. My original
question was:

__________________________________________________ _______

Imagine the following situation: a person sitting in the sports car seat
upside-down (i.e. hanging on seat belts) receives a vertical (up) blow in
the head: 4500N applied at very short duration. Will he survive?

Could you please suggest a reference, which would provide quantitative
information on how much of dynamic loading is transmitted by "dumping" in
the helmet and spine and how much by "elastic" response? Will a substantial
part of the load be absorbed through the acceleration of the system (helmet
+ body, "m * a")?
__________________________________________________ ___

The most valuable information I received was from Dr Adam Wittek from JARI
in Japan. This reference:
Sances et al. (1986) Spinal Injuries with
Vertical Impact, in Mechanisms of Head and Spine Trauma, Eds, Sances,
Thomas, Ewing, Larson, Unterharnscheidt, Aloray Publisher, pp.305-308
describes vertical (head-down) dropping of cadavers. Forces were measured
and pathologies observed. It seems that the impact force of 4500 N is too
low to cause skull fracture or brain damage. Such a force will produce
spinal injuries: damage to vertebrae and intervertebral discs, ligament
disruption and spinous processes fractures.

Other references worth looking at are:
- NHTSA and SAE's web sites
- Winkelstein and Myers 1998, "Determinants of catastrophic head injury" in
Frontiers in Head and Neck Trauma, ed. Yoganandan et al, IOS Press,
Netherlands
- Crit Rev Biomed Eng. 1995;23(5-6):307-409.


Thank you,
Karol Miller

Dr Karol Miller
Senior Lecturer
Department of Mechanical and Materials Engineering
The University of Western Australia
35 Stirling Highway
Crawley WA 6009, AUSTRALIA
Phone: + (61) 8 93807323
Fax: + (61) 8 93801024
Email: kmiller@mech.uwa.edu.au
http://www.mech.uwa.edu.au/kmiller/

---------------------------------------------------------------
To unsubscribe send SIGNOFF BIOMCH-L to LISTSERV@nic.surfnet.nl
For information and archives: http://isb.ri.ccf.org/biomch-l
---------------------------------------------------------------