Engineering Do Axial Forces Affect Bending Moments in Beam Calculations?

AI Thread Summary
Axial forces do not produce bending moments when calculating moments around a point in beam analysis. When summing moments about point C, all forces and applied moments must be considered, not just those to the left. It's recommended to first sketch the moment diagram without excessive values for clarity. Positive bending moments should be treated as clockwise according to engineering convention, and the area under the shear diagram indicates changes in moment. Corrections to support reactions and careful attention to calculations are essential for accurate results.
denk209
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Homework Statement
I need to find everything I can about the beam but I dont know how to do the bending moment.
Relevant Equations
Σ M=0
STAT.png
 
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I tried to get individual moments around point but let say for Mc I get = - Fay*4 + 320*2
so -622.44 for moment in point C
 
Axial (normal) forces passing thru the point about which you are summing moments do not produce bending moments. It is confusing when you show these forces as pointing up and down on the beam.
In taking the moments about C , you need to consider all the forces and applied moments, not just the ones to the left of C.
It is best to draw the moment diagram first as best you can without too many values at first. Also, always treat positive bending moments as clockwise per engineering convention. Remember that the area under the shear diagram between 2 points represents the change in moment between those points. And The slope of the bending moment diagram tangent To the curve at a chosen point is the shear at that point.
Edit: o sorry I wasn’t thinking correctly your method for moment at C is correct. But your Answer is wrong because you need to correct your reactions at supports and watch your simple math.
 
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