Curved and straight combined cross-section structure for energy absorption

Abstract

The force-displacement curve of the energy absorbing structure is generally divided into three stages. And the stable plateau force is important for the energy absorption device. The plateau force of the circular tube exhibits an increasing trend under lateral compressive loading. However, the plateau force of the triangular tube first decreases rapidly and then increases. Therefore, inspired by the geometric features of circular and triangular tubes and their opposite force-displacement curves behavior, this paper proposes curved and straight combined cross-section (CSCC) tubes to obtain stable plateau force. Through the lateral compression test, it can be found that the plateau force of CSCC tube is more stable than that of circular and triangular tubes. And the finite element and theoretical analysis of CSCC tube is carried out. In order to design the force-displacement curve and investigate the energy absorption performance, parametric analysis of the CSCC tube was performed. It can be concluded that the force-displacement curve behavior can be modified by ratio η. When η is around 0.5, a relatively stable plateau force can be obtained. And the plateau force increases with the increase of the wall thickness t and the angle θ of the top curved wall. The required force-displacement curves can be designed by wall thickness. And the CSCC tube can maintain stable plateau force under low velocity impact. Finally, this article proposes the 3D-CSCC structure with CSCC ring as the basic unit. And 3D-CSCC structure has potential applications in sandwich structures.