, /2 | , γf | , /2 | |
, | 0,16 | 1,3 | 0,208 |
2 | 0,09 | 1,3 | 0,117 |
20 | 0,36 | 1,3 | 0,468 |
100(ρ = 3,7 /3) | 0,37 | 1,3 | 0,481 |
1 | 0,03 | 1,3 | 0,039 |
1,313 |
1,313 35,28 = 67,9 .
() 70 , ρ = 25 /3 γf = 1,1 0,07251,1 35,28 = 67,9 .
() 3 . 5,6 0,2 × 0,33 0,20,33251,135,6 = 30,5 .
() 6,3 0,3 × 0,68 0,30,68251,16,3 = 35,34 .
400 × 400 4,20 0,4 0,4251,14,20 = 18,48 .
( 6) 6∙(67,9+30,5+35,34+18,48) = 913,32 .
5- γf = 1,2 51,01,235,28 = 211,68 .
1 2
. (3 ) 1,8 /2.
0,31,8 = 0,54 /2.
: 1,835,28=63,5 , 0,5435,28 = 19,05 .
5- γf= 1,2 551,235,28=1058,4 , 5(51,5) 1,235,28=740,88 .
46,32+913,32+211,68+63,5+1058,4=2293,22 , 46,32+913,32+211,68+19,05+740,88= 1931,25 .
γn = 1,0 N = 2293,221=2293,22 ; Nl = 1931,251 = 1931,25 .
25 A400 . , γb 3= 0,9. Rb =11,50,9=10,35. A400, Rsc =350 . 500.
|
|
.
35, l 0=4200 <20 h = 20 ∙ 400 = 8000 .
φsb φb 15-35 l 0 /h = 4200/400=10,5 Nl / N = =1931,25/2293,22 φb = 0,889 φsb =0,903. φ ≈ (φb + φsb)/2= (0,889+0,903)/2=0,896
:
2,
A = bh = 400∙400 = 160000 2.
4Ø32 A400 (As,tot = 3217 2).
.
αs = RscAs,tot/(RbA)=3553217/(10,35160000)=0,6896;
φ = φb +2(φsb−φb) αs =0,889+2(0,903 0,889)0,6896 = 0,908> φsb = 0,903.
φ = φsb = 0,903 :
Nult = φ (RbA+RscAs,tot)=0,903(10,35160000+3553217)=2794,4 103 =2523,8 .
Nult = 2523,8 > N = 2293,22 , , .
, :
μ=As,tot/A ∙100%=3217/160000 100 = 2,01% >0,4%.
500 8 , sw = 450 < 15 d = 1532 = 480 500 (. 11, ).
.
N = 2293,22 .
25 .. Rb = =11,5 Rbt = 0,9 . A400, Rs =355 .
γfm =1,15, Nn =N/γfm= 2293,22 /1,15=1994 .
R 0 = 0,25 = 250 /2, d =1,6.
γmt =20 /, :
A=Nn/ (R 0 −γmtd)=1994/(250−201,6) = 9,15 2.
a = = = 3,03 ; = 3,10 , A= 3,102 = 9,61 2 's= N/A = 2293,22/9,61 = 239/2 = 0,239 .
. 11. : ; |
: .
(. 11, ) :
,
= h 0 + 50 = 460+50 =510 .
() Ø32400 20 :
, :
As us− Ø32 ;
|
|
Rbond − ,
Rbond = η 1 η 2 Rbt = 2,5∙1,0∙0,9=2,25 ,
η 1=2,5 400 500 η 2=1,0 ≤ 32 (η 2=0,9 36 40 ).
:
1262,7 ,
As,cal, As,ef − , ; α = 0,75 .
= lan+ 50 = 675 +50 = 725 .
H = 800 , , h 1 = 400 .
h 0=80050 = 750 h 01= 400 50 = 350 .
. (b = 1 ) :
Q = 0,5 ( h 2 h 0) bp's = 0,5(3100 500 2750)1 0,239=131,45 H.
Qb,min = 0,5 Rbtbh 01= 0,5 0,9 1350 = H > Q = 157,5 , .
:
:
M I = 0,125 p's (a hc)2 a =0,1250,239 (3100500)2 3100 = 626 106 ͷ;
M II = 0,125 p's (a a 1)2 a =0,1250,239(31001300)2 3100 = 300,1 106 H.
:
As I= M I / (0,9 h 0 Rs)=626106/(0,9750355)= 26132;
As II= M II / (0,9 h 0 1 Rs) = 300,1106/(0,9350355)=2683,7 2.
21Ø14 A400 (s = 3232 2). :
μ I = As /(a 1 h 0)∙100=3232/(1300750)100=0,33 %;
μ II =As /(a h 01)∙100=3232(3100350)100=0,297 %, μmin = 0,10%.
:
s = (a − 100)/(n− 1) = (3100 −100)/(21−1) = 150 ,
n .
1. .. : . - :, 2012. 304 .
2. 63.13330.2012. . . 52-01-2003. .: 2012. 161 .
3. 52-101-2003. - ( 25.12.2003 . 215). .: . 2004.
4.. ( 52- 101-2003). , . .: . 2005. 214 .
5. 20.13330.2011. . 2.01.07-85*. .: ϻ, 2011. 96 .253
6. 22.13330.2011. . 2.02.01-83*. .: ϻ, 2011. 166 .
7. 21.11012009. . - .
8. 21.50193. . - .