Thanks for the reply.
All your calculations are correct. I need to model a cyclic lateral displacement loading on a hollow column with a constant axial load so I need to use shell. I was modeling it and my results showed far less ultimate load capacity compared with experiment even in early...
HI EVERYBODY
I AM MODELING A CONTLIVER BEAM WITH BOX SECTION USING SHELL S4R ELEMENT. INPUT CAN BE SEEN IN THE ATTACHEMENT. i DO NOT KNOW WHY THE RESULTS IS NOT SIMILAR TO THE ANALITICAL RESULTS AT THE YEILD POINT. I MEAN THE RELATION BETWEEN DELTA AND P MUST BE DELTA= PL^3/3EI BUT ITS NOT...