F 8 0 0
_
„
H =■
= 7 6 9 2 ,3 -
S d 0 .8 -1 .3
sm ' T o p ilg a n ku c h la n is h ruxsat e tilg a n k u c h la n is h d a n kam c h iq d i, dem ak
e z ilm a s lik sharti q a n o a tla n tirila d i.
5.2-misol. Burchaklikni list- g a tutashtirish, uchun zaru r bo ‘Igan parchin mixlar soni an iqlansin (5,14-rasm). Qo'yilgan yuk F=75kH. Parchin mix d i ametri d = 1,7sm; [o]=140,0MPa; [ t ] =
110,0 MPa, [a , .]
=280,0 MPa. L ist va burchaklikning uzilmasligi ham tekshirilsin. Boshqa о 'Ichamlar shaklda berilgan. Y e c h is h . P archin m ix la m in g k e s ilm a s lik s h a rtid a n :
F 5 .14-rasm. n > E z ilm a s lik shartidan;
n > , H F n d 2 n = 3 .
n - 2 . KT
U c h ta p a rc h in m ix q o ‘ y a m iz .
B u rc h a k lik b ila n lis tn in g u z ilm a s lik s h a rtin i te k s h ira m iz ;
B u rc h a k lik n in g k o ‘ ndalang kesim yu za si
As = 9 , 8 7 s m 2. L is tn in g k o ‘ ndalang kesim yuzasi
A = 8 ,0 T , 2 =
9 ,6 s m 2 c r, = —
= 8 8 ,0
M Pa < [c r ] >
As S d A1 -
S d D e m a k , m u s ta h k a m lik ta ’ m in la n g a n .