All works only if the model is linear in the element formulation, in the material behaviour formlation and in type of loads. If you don't have these hypoteses you may use an RVE method approach.

Dear Dinesh,

I am afraid You will have to apply dimensional analysis to Your problem in order determine the scaling law relevant for Your problem.  Good guidelines for doing this can be found in the text-book  Dimensional Analysis and Theory of Models by Henry L. Langhaar.