Representative volume element and periodic boundary conditions

[Snobakhti]

Hello all members. My question goes back to the use of representative volume elements for modeling structures and boundary conditions needed to solve RVE in a finite element package. Assume that there is a structure with a representative volume element marked by the solid line in the picture, where symmetric BC is applicable to each side of VE. In this case obviously periodic BC cannot be implemented. In fact, this VE is a quarter of a bigger volume element which is subjected to periodicity to form the whole structure. Is there any appropriate BCs which can be used to model the initial VE for representing the whole structure? Thank you.