Dear all,
I am an undergraduate student, doing my final year project on the buckling of pipe under bending moment. I am wondering if someone could give me some advice regarding this matter. I am trying to solve the problem using finite element method through the use of either Abaqus or MSC Nastran. The problem which I face when using MSC Nastran is that by using the PLATE ELEMENT, the eigenvalue given by the software is too far from the analytical solutions which were suggested by other researchers. I am trying to use Abaqus and I have read in the journal which says that I should allow for the warping degree of freedom. I am wondering if someone could explain to me the meaning of warping degree of freedom (though it has been explained in books, but I don't quite understand it) and which is a more suitable type of element that would do the job well. I am currently trying the SHELL element with small strain (because I read in the manual and it says that this element considers the effect of warping). By the way, how do I choose the analysis step to be used? If I were to use the STATIC RIKS or STATIC GENERAL, then does it mean that I should do it by trial-and-error until I find what is the critical buckling moment? Thanks in advance.