written 6.1 years ago by |
to back in opposite site of gusset plate 2)Angle place same side of gusset
Angle are tack bolted & provided wotj min of two bolts
Given P=178KN
l=3.05m
leff=0 8×3.08
=2464mm
consider fed=150mpa
Pd=Ae×fcd
178×103=Ae×150
back to back connection Ae=1186.67mm2 Area required
Area of each angle=1186.672=56.33mm2
Assume fcd=90mpa
Pd=Ae×fcd
178×103=Ae×90
Ae=1977.78mm2
Area of each angle = 1977.782=988.88mm2
select Anlge=×80×50×10
A=1202mm2
Area provided =1202×2=2404mm2
γxx=√$IxxA γuu=√IuuA
Iuu=22.10×104mm4--steel table
Iyy1=Iyy1+Iyy2
=2(Iyy+Ah2)
=2(22.10×104+1202×(102+13.2)2)
Iyy=1.23×106mm6
γyy=√1.23×1062404
γyy=22.63mm
λ=kLγyy=246422.69=108.56
100 107
108 fcd
110 94.6
110−100110−106.56=94.6−10794.6−fcd
101.44=−12.494.6−fcd
-17.856=946-10fc
fcd=96.38 N/mm2
Pd=A×fcd
=2404×96.38
Pd=231.71 KN =178 KN hence safe
Case second
angle connect same side of gusset plate
Iyy=Iyy1+Iyy2
=2(22.1×104+1202(17.2)2)
Iyy=860×87×103mm4
γyy=√860.87×1032404=18.92mm
λ=246418.92=130.20
130 743 140=130140−130.20=66.2−74366.2−fcd
fcd=74.13N/mm2
Pd=2404×74.13
=178.22KN>178 hence safe