Compactness for $GSB{V}^p$ via concentration-compactness

Motivated by variational models for fracture, we provide a new proof of compactness for $GSB{V}^p$ functions without a priori bounds on the function itself. Our proof is based on the classical idea of concentration-compactness, making it transparent in strategy and simple in implementation. Further, so far as we are aware, this is the first time the connection to concentration-compactness has been made explicit for problems in fracture mechanics.