Failure analysis of collapsed parking garage building due to punching

•Structural analysis of collapsed roof flat slab using Linear finite element analysis (LFEA) and Non-linear finite element analysis (NFLEA)•Assessment of punching capacity using design equations from Eurocode 2 and Critical shear crack theory (CSCT) with LFEA.•Application of the NFLEA with CSCT for the assessment of the punching capacity of slab-column connections in collapsed flat slab.•Considering of membrane forces on the prediction of punching capacity of slab-column connections in collapsed flat slab.