V-
k o e ffits ie n tla r
h i в
nisbatga bogMiq holda 6.1-jadvaldan o lin a d i.
T o ‘g ‘ ri t o ‘ rtb u rc h a k li ke s im uchun m u s ta h k a m lik va b ik r lik s h a rtla ri:
r _ = — ^ < [ r ] ;
(6 .1 4 )
в =
_ ±r±6
a h e 2
ЪЛ
p h e 3G
(6 .1 5 )
B u ra la y o tg a n s te rje n n in g k o ‘ n d a lan g k e s im i teng y o n li tra p e ts iy a shak-
lid a b o ‘ lsa, h is o b la s h ja ra y o n id a uni e k v iv a le n t boMgan t o ‘g ‘ r i t o ‘ rtb u rc h a k
b ila n a lm a s h tirila d i (6 .9 -ra s m ). B u n in g u c h u n
tra p e ts iy a n in g o g M rlik m a rka zi С dan u n in g y o n
to m o n la rig a C B v a C D p e rp e n d ik u la rla ri tu s h iri-
la d i. В v a D n u q ta la rid a n v e r t ik a l c h iz iq la r
o 'tk a z ila d i.
H o s il boM gan
abed
t o ‘ rtb u rc h a g i iz la n g a n
e k v iv a le n t (te n g k u c h li) t o ‘ r tb u rc h a k d ir . S hu
t o ‘ rtb u rc h a k d a n fo y d a la n ib te n g y o n li tra p e t-
siyada h o s il boM adigan eng k a tta u rin m a k u c h
la n is h v a b u ra lis h b u rc h a g in in g ta q r ib iy q iy m a t
la r in i a n iq la sh m u m k in .
K o ‘ ndalang k e sim i e llip s shakliga ega boMgan
sterjen buralganda undagi m aksim al u rin m a k u c h
la n is h la r k ic h ik y a rim o ‘ q !a r b ila n e llip s n in g ke-
sishgan nuqtasida h o s il boMadi (6 .1 0 -ra sm ).
6.9-rasm.
Buralishdagi qarshilik
momenti Wk, sm3
Eng kalta urinma
kuchlanish hosil bo’lgan
nuqtalar
h
b
a
P
У
1
0,20S
0,141
1
1,5
0,231
0,196
0,859
1,75
0.239
0,214
-
2,0
0,246
0,229
0,795
2,5
0,256
0,249
-
3,0
0,267
0,263
0,753
4,0
0,2X2
0,2X1
0,745
6,0
0,292
0,299
0,743
8,0
0,307
0,307
0,743
10,0
0,313
0,313
0,743
00
0,333
0,333
0,743
Jk= phb3
Wk = a lib2
Uzun tomonlur
o'rfasi;
M.
;
,K
Kalta tomonlar o'rtasi
т — У Tm.i\ ■
Burchaklarda kuchlanish
nolga teng.
Fra
w
Щ
■к=-
h<% + f>& -
6>r -
Wk|-2 h o b ()6|
Wk
2
=
2
h(i bn
8 2
Uzun (omonning
•
Мл
о rtasi r. = —- ;
W
" 1 1
Kalta lomonning
о rtasi r, = —-
- IK.,
Ichki burchaklarda, materialning
oquvchanlik chegarasiga yaqin miqdorda,
kuchlanishlarning yuqori darajadagi
kontsentratsiyasi yuz beradi.
Burchaklar r radiusii yoyga ega bo'lsa,
konlsenlnitsiya koeffitsienti
a , =
1.74?
bo'ladi
‘
64 '
I
W =
irb 'h
1 б ~
Kichik yarim o'qlarning
tashqi nuqtalarida
M,; .
r“ "
wt '
Katta yarim o'qlarning
lashqi т, =
m
nuqtalarida
_ ™ > ;(i-g 4)
1
16(»r + l)
_
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