' ( ), ( 42).
43. ǒ ,
' . , . ' , , . ' .
, ' . '. ' ' ' , ' '.
: , . 1759.487, , 12 , 7 .
, , . , 100, σΒ, , , , 10 σΒ, . , 5.6 : σΒ mn = 5 100 = 500 ; σT = 6 500/10 = 300 .
( 1759.4 87) 4 5.
4.
σΒ, | |||||
min | max | σ, | |||
.6 | ; 10 | ||||
4.6 | |||||
5.6 | 3; 35 | ||||
6.6 | 35; 45; 40 | ||||
8.8 | ; 38 | 20; 35; 45 | |||
10.9 | 402; 40 | 35; 38 |
5.
σ F, | ||
20; 35; 45 35; 38 |
' ', '.
ϳ : , .
|
|
, , d = 12 , Ρ = 1,25, l = 60 4.6 : 12 x 1,25 x 60.46 7805 70. 1759.0 87. , 3.6, 14.9.
. 100, σF, , . , 4 σF = 4 100 = 400 ( , ), 14 σF = 14 100 = 1400 ( 35, 40).
, , , d = 12 , Ρ = 1,25 8 : 12 x 1,25.8 5927 70.