Hello,

Making my own structure and running non-linear elastic static study. I have defined my own stress strain curve and ran my simulations. Adding pressing to certain rectangular area on my structure, I have made 3 tables, each have exactly the same forces/geometry/Material properties, and the only thing changing is the time steps.

Now in each table I have 5 rows, with each row I have changed the mesh size from finest to coarsest. (Attached is a file where it will make all the above easier to understand and see).

In the last column, I have calculated the Force/Load by hand, by multiplying the pressure with the area of the rectangle that I applied it to. I.e I have set the max. time to 5 seconds, expecting the model to fail before it reaches the max. (A column shows the max time step reached).

My two critical questions are:

1- From the maximum time step reached for each mesh, I am calculating that pressure on that certain time. Hence, with each single time-step, a fixed load is considered. Is that correct?

2- Before obtaining my tables, I would have thought with very time the element size is smaller  (Finer) a max. step reached would be higher towards the 5 second time set. And should have a consistent Load, either increasing or decreasing. (Shown in the last column). Is it normal being random, or am I calculating it wrong, or something else I am doing, is wrong?

Please, anyone who is sure or have a certain explaintion let me know, as I can not seem to understand the coming results.

Many thanks in advance.