Stress analysis of a clamped beam
 

Dear all,

I am currently validating test cases of a clamped beam under several types of load:

- concentrated load at free end of the beam
- linear distributed load
- polynomial distributed load
- discontinuous load (constant load q for a < x < (a+b), 0 otherwise)

all this with solver solidDisplacementFoam and groovy boundary conditions.

I reused the clamped beam available in solver solidEquilibriumDisplacementFoam for my case, refining the mesh as follows : 50 cells with a grading of 100 along X (beam axis), 50 cells along Y and 1 cell along Z (2D case).

As for the boudary conditions, I used groovy tractionDisplacement conditions for the free end of the beam and for the top and bottom surfaces. The other end of the beam is clamped with a fixedValue condition (see attached D file for the example of the linear distributed loading).

Displacement and axial stress results seem to be OK, except at the clamped end of the beam (x=0), where a stress discontinuity is systematically observed whichever the case (see attached screenshots). Close to the end, the stresses become consistent with the analytical results, but I cannot get rid of this "edge effect"...

Would someone have any idea of what happens here?...

Thanks in advance

Christophe