ABSTRACT
The elastic buckling of a thin-walled cylindrical tube containing an elastic infill is addressed in this paper. It is widely known that the local buckling of a hollow tube can be enhanced by providing a rigid infill (usually concrete), but it is possible to increase the local buckling stress using a less-rigid and less-dense infill that can optimise the strength to weight ratio of the member, which may be advantageous in aerospace applications. The elastic buckling stress is determined using a Ritz-based approach as a function of the stiffness of the infill, and an approximation is proposed for the minimum local buckling stress.
