Hi Arshad,

I think that's normal, because stiffness of your structures are different which lead on different displacements. As a result of your different displacements, you get different strain.

Best regards,

Oguzhan Yalcin

read st. venant's principle

Since the force is statically determinate, the force transmitted will be independent of the stiffness of the structure.

Mir Aamir Abbas I totally agree with you i.e I am confused why are strains are changing in both the cases.

Oguzhan Yalcin that would have been true if the parts are in parallel but in this problem both the parts are in series.

Hi Arshad K a. Physically, the two forces would be equal but in a nonlinear analysis, the law of statics are not obeyed exactly; they are obeyed only to some degree of accuracy. The force and moment residuals would not exactly be zero. If the residuals are not exactly the same (it is highly unlikely that they would be equal), the forces would not be the same. Since the mesh of the cantilever is the same in both cases, the stresses are different because the forces are different because of the nonlinear force and moment residuals. Hope this helps.

I mean that different cross sections of the shafts occur different (z rotation) bending on the main profile which can change the strain. The hollow shaft makes more bending angle (z rotation) on the main profile than the solid shaft.

The difference could be that the 2 models did not mesh the same. You can see from the pictures that they are different in the region of the notch. This can be caused by the difference in meshing between the hollow and solid shafts. Try varying the thickness of the hollow shaft wall. Also try to force the model to start the mesh from the other end, then the difference will be mostly at the shaft end. However, a 5% difference is perfectly acceptable and is within the accuracy of the calculation.

if not hyperstatic the loads are going to be the same