SMEAR property in PCOMP card

[Rinos]

What is the meaning of smear in PCOMP card, to define orthotrophic material lay-ups? In which situation, this smear option is used? When I see the Nastran help, it says ply effects are smeared and the stacking sequence are ignored. If stacking sequnce are ignored, how the analysis will be right? Appreciate, experts thro some lights on this topic..

 

[GBor]

A "smeared" property uses sound, laminated plate theory to reduce the individual ply properties using the angles of the lay-up to a single plate with equivalent properties. It speeds up the calculations, but you have to back the individual ply stresses and strains out after the analysis is performed (your post-processor may do this for you).

I think Materials Sciences Corporation in Fort Washington, PA has an online calculator that will developed "smeared" properties for you. If not, you can write your own...it isn't terribly difficult and there are several books that will help with the math.

Garland E. Borowski, PE
Borowski Engineering & Analytical Services, Inc.
Lower Alabama SolidWorks Users Group