Enhanced vibration correlation technique to predict the buckling load of unstiffened composite cylindrical shells

•The relationship among the applicability of the VCT, the convergence of this technique and the knockdown factor to be estimated is explored.•A load factor multiplying the linear buckling load is proposed towards enhanced VCT buckling load estimations for unstiffened composite cylindrical shells.•The robustness of the devised approach is demonstrated through an extensive numerical study and by revisiting experimental results.