Quick Beam Stress Question

[Cheyne]

I am interested in the stress results of combined stresses in beam elements... in my attached example, I'm comparing the results from a "3166. Beam EndB Max Comb Stress" to the "3167. Beam EndB Min Comb Stress" output sets. The "3166...Max..." results shows a max stress at +1840 psi, and the "3167...Min..." shows a min stress at -2223.76 psi.

Is the max output set showing the true max stress (1840 psi). Or, is the higher absolute value of the max and min output sets (assuming the negative sign denotes compressed elements) the actual max stress ( ABS|-2223.76| psi)?

Thanks in advance.

See pics in the attachment

http://www.martinezandturek.com

 

[Cheyne]

FYI, I realize negative stresses implies compression in general analysis, but in the femap world, I wanted to verify this notion. In this case, it is counter-intuitive that the "Max" stress isn't really my max stress if my "Min" output set has greater compressive stresses. I'm simply verifying.

I want to make it clear, my question is to better understand result outputs from FEMAP, and not to ask general stress analysis questions.

Hope I didn't waste anyone's time with a common sense question.

http://www.martinezandturek.com

 

[BlasMolero]

Dear Cheyne,
For beam elements tensile stresses are given a positive sign and compressive stresses a negative sign. The SA-MAX, SB-MAX, SA-MIN, and SB-MIN stresses are the maximum and minimum combined bending and axial stresses for each end, the MIN is related with compressive stress sign, not with the mínimum value.
Best regards,
Blas.

~~~~~~~~~~~~~~~~~~~~~~
Blas Molero Hidalgo
Ingeniero Industrial
Director

IBERISA
48011 BILBAO (SPAIN)
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[rb1957]

tension is +ve, compression is -ve ... +ve numbers are bigger than -ve ones

"Is the max output set showing the true max stress (1840 psi). " ... it should be

"In this case, it is counter-intuitive that the "Max" stress isn't really my max stress if my "Min" output set has greater compressive stresses." ... max stress is purely the biggest +ve stress (or the smallest -ve stress, the one closest to zero); min stress is the largest -ve stress (the one furthest from zero) ...

Quando Omni Flunkus Moritati

 

[Cheyne]

Gentlemen,

Much appreciated.

-Cheyne

http://www.martinezandturek.com