Compression and bending on a cross section,how to make sure its static

AI Thread Summary
The discussion centers on analyzing a rectangular steel cross-section under bending and compression, focusing on ensuring static equilibrium. The initial approach to equilibrium equations is questioned, particularly regarding the relationship between compressive and tensile forces. A corrected equation is proposed, emphasizing that the axial force from tension must equal the axial force applied to the section. A clarification is made regarding a typo in the equations, specifying the correct terms to use. Understanding these dynamics is crucial for accurate structural analysis.
cesaramorim
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The problem is the following, i have a rectangle as a cross section of steel, which is bended and compressed.. i want to use the equilibrium equations to make sure its static, but since the compressive force and the traction force aren't equal, the equilibrium equations make no sense

here's a diagram explaining it

http://imageshack.us/photo/my-images/341/6p7g.jpg/

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Thanks for reading
 
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cesaramorim: No, I think your first equation instead should be, N = Fc - Ft.

And your second equation should not contain two plus signs.
 
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that's exactly it, because if you have axial force on the bend, it can't be 0, instead, the sum of axial forces caused by tension must equal the axial force applied on the section, i was misunderstunding with pure bending on concrete structures where that equation is valid because N is 0 in that case.

thank you very much

ps: yes the second equation has a typo, it means Fc*d1, instead of Fc+d1
 
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