:
,
R=17=1,7/2
RBt= 1.2 =0,12 /2
B2 = 0,9
RB= 1,7*0,9 =1.53/2
Rbt = 0.12*0.9 = 0.108 /2
A-3
Rsc=365=36,5/2
-1
l0/h<20
l0/h=3.6/0.3=12<20, , .
N/N
N/N=490,3/608,7=0,8
fo/h Nn/N b sb
b=0,87
sb=0,89
u=0.01
as=RSc*u/Rb
Rsc- , u- , Rb-
as=36.5*0.01/1.53=0.24
| . |
| . |
| 6 270103 31 13 |
=+2(sb-b)s
=0,87+2(0,89-0,87)*0,24=0,88
<sb 0.88<0.89
As+As!= N/-Rbbh/Rsc
As+As!=608.7/0.88-1.53*30*30/36.5=-18.7
N-
(-
Rb-
Rsc-
b h-
, , ( ) .
, > 250 16 , 4016 -3As=8,042
u=(As+A/s)100%/bh
As+As - 8.04 2
b h-
u=8.04/30*30*100%=0.9%
u=0,05%
u=3%
.
dsw>0,25 ds
d-
dSw=0,25* 16=4. 04 -1
S<20 ds
d -
S<20*16=320 , S=300
3-
-1
. 1- 1-40;
I -
b-b-20
- =300
|
|
|
( 10 , , 20 )
L=4600-40=4560
L=300-20=280
, 20 5 . 4 - ,
| . |
| . |
| 6 270103 31 13 |
n=I/300=14
4240-14*300=40
4-
-1
| . |
| . |
| 6 270103 31 13 |
, -1, .
, , .. 04 -1, 300 ;,
() -1, 4 -1.
60
5- .
6- -1
7-
| . |
| . |
| 6 270103 31 13 |
250 , 50 500 100 500 .,
: £ 20; - 304 -111, -11, 12 40 , 16-25 ; -1, -111 -1, dsw>0,25 ds ( - 0.25 ds ( s<15 ds), ds- .
3. ;
) - cnoeiyi 20 15 ;
) 10 9 15 12 . , , 10
) 400*400 4 , , 400;
) .
|
|
|
) () ( 4-) ,
) , . , . , . 11;12- 1/51 1/81
