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Steel Columns Design Problem 2 - Design a steel column:
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Design a steel W12 column using LRFD for a factored load of 813 kips.
The column is 50 feet long with pinned ends (rotation permitted, translation prevented).
The weak axis of the column is laterally braced at midheight.
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1. From the steel columns submenu open the compressive strength for flexural buckling of non-slender sections calculation, NSFBCompStrength.aspx.
Input the "Title" of the calculation, the "Designer/Checker" information.
Then from the steel shape section properties submenu open the W section properties table, WShapeTables.pdf.
Starting with a W12 x 120 section, enter the variables click on the "Calculate" button and read the results. The capacity is 801.727 kips which is less than 813 kips.
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2. Next, try a W12 x 136 section. Enter the variables click on the "Calculate" button and read the results. The capacity is 924.336 kips which is greater than 813 kips.
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3. Next determine KLy. Using rx/ry = 1.766, KLy = 50/1.766 = 28.31.
Try a W12 x 152 section. Enter the variables click on the "Calculate" button and read the results. The capacity is 879.290 kips which is greater than 813 kips.
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4. Summary
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The lightest W12 section is a W12 x 152, with a capacity of 879.290 kips.
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