1
2011
..
624.012
2903 /- . -.; . ,,. , 2010
1 , , .
, 2903 .
: . . , .
() . ( 7 ) , .
18 , 70 % , - () .
, .
:
- ; ; ;
:
- ( 3, 5, 6, 7), .. , .
. | ||
. | ||
() | ||
1
.
:
- ∑y = 0
|
|
N = Nb + Ns = sb Ab + ss As
, . .
εb = εs
sb = εb Eb; ss = εs Es εb = sb /Eb; εs = ss/Es
ss/Es = sb /Eb
s
ss = sb Es/Eb Es/Eb= α
ss = sb α
N = sb Ab + sb α As = sb (Ab + α As) = sb Ared
sb = N /Ared
ss = α N /Ared
Es ≈ 200000
Eb - 2000040000
ss 6-8 sb.
sb = M /Wred = M∙yi /Ired
ss = α M /Wred = α M∙ys /Ired
y i sb = N/Ared + M∙yi/Ired
ss = α (N/Ared + M∙yi