, .
, .
:
αm= /(γb2*Rb*b*h²ₒ)=(86,5*1000000)/(0,9*11,5*1800*370²)=0,0339
:
ξ=1-(1-2* αm)½= 1-(1-2*0,0339)½=0,0345
X= ξ* hₒ=0,0345*370=12,77< hf=70
.
:
s= /(Rs*hₒ*(1-0,5* ξ))= 86,5*1000000/(365*370*(1-0,5* 0,0345))=652,00 (²)
2ȹ22 A III s=760 ²
:
αm= /(γb2*Rb*b*h²ₒ)=(54,0*1000000)/(0,9*11,5*1800*370²)=0,0212
:
ξ=1-(1-2* αm)½= 1-(1-2*0,0212)½=0,0214
:
s= /(Rs*hₒ*(1-0,5* ξ))= 54,0*1000000/(365*370*(1-0,5* 0,0214))=404,00 (²)
2ȹ18 A III s=509 ²
.
:
αm= /(γb2*Rb*b*h²ₒ)=(67,9*1000000)/(0,9*11,5*200*380²)=0,227
:
ξ=1-(1-2* αm)½= 1-(1-2*0,227)½=0,261
.
:
ω=0,85-0,008* γb2*Rb=0,85-0,008*0,9*11,5=0,767
= 
=0,63
ξ=0,261< 
=0,63
:
s= /(Rs*hₒ*(1-0,5* ξ))= 67,9*1000000/(360*380*(1-0,5* 0,0261))=571,00 (²)
:
s=371/2=286 ²
1
s=286/1,8=159 ²/
3I-200 3500 s=196,0 (²)
5I-100
:
:
αm= /(γb2*Rb*b*h²ₒ)=(54,0*1000000)/(0,9*11,5*200*380²)=0,1811
:
ξ=1-(1-2* αm)½= 1-(1-2*0,1811)½=0,201
:
s= /(Rs*hₒ*(1-0,5* ξ))= 54,0*1000000/(360*380*(1-0,5* 0,201))=439,00 (²)
:
s=439/2=220 ²
1
s=220/1,8=122 ²/
3I-200 3500 s=126,0 (²)
|
|
|
4I-100
2ȹ10 A I
:
αm= /(γb2*Rb*b*h²ₒ)=(11,71*1000000)/(0,9*11,5*200*370²)=0,0413
:
ξ=1-(1-2* αm)½= 1-(1-2*0,0413)½=0,0422
:
s= /(Rs*hₒ*(1-0,5* ξ))= 11,71*1000000/(225*370*(1-0,5* 0,0422))=143,7 (²)
2ȹ10 A I s=157 ², .
.
:
( ) Rb=11,5 .
Rbt=0,9 .
Eb=27000
I Rsw=175 .
Es=210000
