Hi - I'm modelling a flat top pressure vessel that is effectively a closed cylinder and the thickness of the flat head is less than the thickness of the cylinder itself. So I am applying internal pressure within the cylinder and it will obviously start to stress more at the flat head due due it being thinner. All is good so far as model is working and the max von mises stress is where I expect it to be. I would now like to ascertain what pressure would cause the vessel to 'burst'. Is this possible to do by looking at how many of the gauss points in the area of the head have AC YIELD so I could effectively count these and compare with number of total gauss points and if over a certain percentage I can extrapolate the time that this happened and hence interpolate to the pressure (which is being applied incrementally with time)? Or is there another way? also does anyone have any suggestions as how to analytically verify the results that I get ? thanks