Vol.3, No 15, 2003 pp.1147-1150
UDC 531.353:611.91(045)
Invited Paper
CONTACT STRESS BETWEEN THE RUBBER BALL
AND THE HEAD
Dušan Mikičić
Faculty of Electrical Engineering, Belgrade, e-mail: mikicic@etf.bg.ac.yu
Abstract. Mechanical injuries of the head occur because of the following:
1. Contact stresses between the head and some other solid bodies, when
mechanical stresses exceed endurance of the skin and skull bones 2. The
great accelerations (frequently decelerations) which cause pressure oscillation
and consequent pulsing in brain mass. This can occur even if foreign body
is not in touch with injury. This paper represents biomechanical model
for the calculation of impact force F and contact stress ? between a ball
and a head. This work contributes 2 absolutely new formulas for force F,
and stress ?. These formulas are first step in biomechanical analysis of
further consequences (of brain injuries) to the scull bones and skin.
KONTAKTNI NAPON IZMEĐU GUMENE LOPTE I
GLAVE
Mehaničke povrede glave nastaju zbog: 1. Kontaktnih naprezanja izmedju
glave i drugih čvrstih predmeta, kada mehanički naponi prevazilaze izdržljivost
kože i kostiju lobanje. 2. Drugi razlog za mehaničke povrede glave su velika
ubrzanja (češće usporenja) koja uzrokuju pulzaciju pritiska u moždanoj
masi. Ovo se dešava čak i u slučajevima kada strano telo ne dopre do povređenog
mesta. U ovome radu biće prikazan biomehanički model za proračun udarne
sile i kontaktnog naprezanja između lopte i glave čoveka. Pri tome
su korišćene Hertz-ove formule za kontaktna naprezanja dve kugle. Proračun
sile F i kontaktnog naprezanja ? je prvi korak u biomehaničkoj analizi
daljih posledica na kožu i kosti lobanje. Nakon toga sledi procena posledica
na unutrašnju strukturu mozga.
