Design and Assessments of Gradient Chamfer Trigger for Enhancing Energy-Absorption of CFRP Square Tube

It is proposed to use the gradient chamfer trigger method to explore the axial crush response phenomenon of Carbon fiber reinforced plastic (CFRP) composite materials square tube. A reliable non-linear progressive damage failure model based on numerical simulation method is established for verification and parameter evaluation. The discrepancy in the crush response between the tube of gradient trigger (GT) and uniform thickness (UT) reveals the exceptional amelioration effect of GT design on the crush behavior of the composite tube. Through the parameters analysis of the trigger chamfer of each layer, the gradient distance and the layer number of GT, the improvement mechanism of the GT design is extensively revealed. Numerical results show that the gradient chamfer-triggered interlayer distance has the most significant improvement in energy absorption when the structural collapse process exhibits stable progressive failure behavior. And the specific energy absorption of GT structure also showed an upward trend when the number of layers triggered by gradient chamfering increased. When the chamfer angle of the inner layer of the GT structure is smaller than that of the outer layer, it is most beneficial to improve the specific energy absorption.