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UNDERHUNG CRANE BOTTOM FLANGE LOCAL BENDING |
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| Crane runway beam section |
Label
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Label
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d |
= |
Label
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[mm] |
bf |
= |
Label
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[mm] |
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tw |
= |
Label
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[mm] |
tf |
= |
Label
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[mm] |
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k |
= |
Label
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[mm] |
k1 |
= |
Label
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[mm] |
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| W section yield strength |
Fwy |
= |
Label
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[MPa] |
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| Effective Cantilever Length |
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Assume wheel width = 1" and point load Pw acting at 0.5" offset from flange tip |
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For W shape |
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La |
= |
bf /2 -k1 - 0.5"
(12.7mm) |
= |
Label
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[mm] |
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For S shape |
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Flange thickness at toe |
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tf2 |
= |
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= |
Label
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[mm] |
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Radius of fillet |
R |
= |
k- tf2 |
= |
Label
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[mm] |
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La |
= |
0.5 x ( bf - tw ) - R -0.5"(12.7mm) |
= |
Label
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[mm] |
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Effective Bottom Flange Bending Width |
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The effective bottom flange bending width is taken as
be=2xLa as per
answer to Bottom Flange Bending Capacity by David T. Ricker P.E. in AISC Modern
Steel Construction Feb 2005 |
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Effective flange bending width |
be |
= |
2 x La |
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= |
Label
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[mm] |
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Flange Thickness at Web Toe |
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For W shape |
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t |
= |
tf |
= |
Label
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[mm] |
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For S shape |
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t |
= |
tf2 |
= |
Label
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[mm] |
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Wheel load one side of flange |
Pw |
= |
Pmax / 2 x a (impact factor) |
= |
Label
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[kN] |
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Factored bending moment |
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Mf |
= |
1.5 x Pw x La |
= |
Label
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[kN-m] |
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S |
= |
be x t2 / 6 |
= |
Label
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[mm3] |
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Mr |
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0.9 x S x Fy |
= |
Label
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[kN-m] |
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ratio |
= |
Mf / Mr |
= |
Label
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Label
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