Cutting and crushing of square aluminium/CFRP tubes

Square CFRP tubes were wrapped externally with aluminium sheets and crushed quasi-statically in the axial direction to investigate the effect of aluminium sheet-wrapping on the energy absorption of CFRP tubes. Moreover, a specially designed and manufactured platen with cutting blades was employed, as a new energy dissipating mechanism, to simultaneously cut and crush both CFRP tubes and aluminium sheet-wrapped CFRP tubes. Notches were introduced at one end of some tubes which were crushed by a platen with blades to control the location of the failure. Experimental results showed that the deformation mode of CFRP tubes and aluminium sheet-wrapped CFRP tubes that were crushed by a flat platen or by a platen with blades was a combination of splaying progressive and transverse shearing failure mode. By wrapping CFRP tubes with aluminium sheets and using cutting blades, the mean crushing force and energy absorption increased by up to 70%. The crushing response of tubes without notches crushed by a platen with blades was similar to those tubes crushed by flat platens. Tubes with notches crushed by a platen with blades had a lower initial peak force, higher mean crushing force, larger energy absorption and higher specific energy absorption in comparison with counterpart tubes crushed by flat platens.