Dear all,
I have implemented 3D corotational beam finite element according to Crisfield's approach ("A consistent co-rotational formulation for non-linear, three-dimensional, beam-elements" - 1990) in MATLAB. I am able to obtain the results exactly for Example 1 - A cantilevered beam with a concentrated moment applied at the free end. But for the second example - A 45 deg bent beam with a concentrated shear load applied at the end - though I am able to get the solution close to what is mentioned in the paper, my code is taking approx. 70 iterations on an average to converge in each load increment whereas the author mentions it only takes about 6 iterations for each load step. I am not sure where I am going wrong. Please help me in this regard.
It would be great to know where my mistake can be in general. I am really confused though I am getting correct solution, my code is converging very slowly compared to what is given in the paper.
Thanks.
Sunil JYV.
3d corotational beam element after MAC
hi sunil
very likely you have a mistake as to how you update the rotation d.o.f.
the first example you refer to is in effect a two dim. problem so the activation of the rot. algorithm
does not happen however the 45 deg bent is truly a three dim. problem .
so my guess is the rotation update algorithm might be the culprit
regards ikalo