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2014
1
1. 1. .
1.2. .
1.3. ( 1 ).
1.4. .
2.1.
2.2. .
2.3. .
2.4. .
2.5. .
2.6. .
2.7.
2.8. .
2.9
. 1 .
l×lk= 6,0 × 5,85 . γ=1,0. =13,5 /2. 25. 75%. , .
S= l / 3 = 6,0 / 3 = 2,0 . : l2:l1 ≈ lk:S = 5,85:2,0 = 2,925>2, .. .
25 Rb= 14,5 . γb1=1,0 , , Rb= 1,0∙14,5 = 14,5 .
:
h=70 ;
:
h = 1/12 l= 1/12*5850=487,5 , h =500 ;
b = (0,40,5)∙ h = (0,40,5)*500=200- 250 , b = 220.
1.1. .
: l1 = S- 1,5∙b - 0,05 = 2,0 - 1,5∙0,22 - 0,05 = 1,62
: l2 = S- b = 2,0-0,22 = 1,78 >l1 = 1,62
.
) ( γf= 1,1):
1,1∙0,07∙25 = 1,93 /2;
1,1∙2,5 = 2,75 /2
: g0 = 1,93+2,75 = 4,68 /2
) ( γf= 1,2): p0 = 1,2∙13,5 = 16,2 /2
) 1 γn= 1,0:
q = γn∙(g0+p0) = 1,0∙(4,68+16,2) = 20,88 /2
( 1 ).
: 
: 
: 
|
|
|
: = 2 = 4,13 ∙.
( ).
1.4. .
1= 5,07 ∙;
b= 1000 . ξ = 0,25
.
h= h0+a= 39,46+24 = 63,46 . h = 70 .
.
( 1 )
) .
1= 4,93 ∙; b = 1000 .
= 24 , h0 = h =7024 = 46 .
: 
(+16,5%)
) :
= 4,73 ∙; b= 1000 ; = 24 ; h0 = 46 .
,
: 
; As=335 2 (+4,3)
) .
M2=-MC =4,18 ×; b =1000 ; a =24 ; h0 =46 .
: 
; As=287 2 (+3,4%)
) A (. . 3).
As ³0,50 As1 =0,50×335,6=167,8 2.
: 
; As=189 2 (+11,2%)
