, , , . () .
● , :
f γf = l; fu , , , , fu = l/500, l/600, l<6 l/200, 6 <l≤7,5 3 , l>7,5 l/250 . .
, , . , , , .
, EbIred. (. 7.3, ), , . (. 7.3, ), , (. 7.3, ), , . . , .
, ; (l/r)x , .
. 7.3.
, l/r ( ) (7.22) , , , . . , , . . (7.22)
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φm , , : φm = 5/48, φm=l/12, φm=1/8; l/r .
l/h<10 [1]. ftot , fm fq.
● . ,
, ; φb1 , (-) , φb1 = 0,85; φb2 , , φb2=1, φb2=2...4,5.
, , . , , : , .
. f3 (. 7.4) , . (7.23) (7.24),
.
εb εb , , , εb = σb/Es, ε′b=σ′b/Es; σb (σ6, σ8, σ9) ; σ′b , , .
. 7.4. ,
(. . 7.4)
2 .
(φb2 = 1)
, :
■ . , (. 7.5, ). , , . , , (. 7.5, ). , , . , , , (. 7.5, ).
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. 7.5.
(. . 7.5, ) . .
, , . . . , εsm, εbm m.
ds. , . 7.5, .
Δlb Δls ds.
, εsm=Δls/ds εbm=Δlb/ds, (7.31)
εsm εbm :
ψs , , ψs=εsm/εs; ψb , , ψb = εbm/εb = 0,9; Eb,pl , Eb,pl=Ebv; v , , v = 0,45, v = 0,15 (. . 1).
(7.33) (7.34) (7.32),
, , , (. 7.5, ):
z ; b ; b = bm.
(7.37) , , , , , ψs, , ψb, , v. ψs, v .
Ntot ( ), (7.37)
, , ( Ntot), .
(7.37) (7.38) ψs z [1].
, .
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(l/r) ; (1/r)2 ; (1/r)3 ; (1/r)4 , , (7.26).
(7.39) .
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3 ,
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4.
5.
. 6.
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7.
8. .
9. , .
10.
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11. , .
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13.
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