Learning Forum

[userzff067]

When using APDL to create a cantilever beam with beam188 elements and a circular cross-section, I am trying to output the shear strains EXY and EXZ at the cross-section.

Since beam188 represents a Timoshenko beam, theoretically these values should remain constant along the entire length of the beam. However, every time I calculate them, the shear strains are coming out as 0. I have already set KEYOPT(4) = 2 to obtain shear stresses, but these shear stresses are varying across the cross-section, whereas I expect the shear strains at the cross-section to remain constant.

Could someone kindly provide a method to set up the output of shear strains so that they are not zero?

Alternatively, what is the relationship between the shear stresses currently output and the constant shear strains at the cross-section? If possible, please provide a formula. Why are the shear strains varying when they are expected to be constant?

[Erik Kostson]

Hi

 

' but these shear stresses are varying across the cross-section, whereas I expect the shear strains at the cross-section to remain constant.'

See books and search (shear stress variation through thickness max at centre line and zero on the extreme fibres):

https://profkodali.blogspot.com/2010/09/shear-stresses-in-beams.html

All the best

Erik

[userzff067]

I hope you can give me some help, it's really important to me。 the cross-sectional strain should be a constant and not 0. How to obtain the cross-sectional strain? When the entire beam is subjected to concentrated stress at the end, there will be shear strain caused by bending.

[userzff067]

But the cross-sectional strain should be a constant and not 0. How to obtain the cross-sectional strain? When the entire beam is subjected to concentrated stress at the end, there will be shear strain caused by bending.

[userzff067]