CRASH ENERGY ABSORPTION OF MULTI-SEGMENTS CRASH BOX UNDER FRONTAL LOAD

Abstract

Crash box designs have been developed in order to obtain the optimum crashworthiness performance. Circular cross section is first investigated with one segment design, it rather influenced by its length which is being sensitive to the buckling occurrence. In this study, the crash box with multi-segments design is investigated and the deformation behavior and crash energy absorption are observed.  The crash box modelling is performed by finite element analysis on cylindrical crash box with multi segments design. The numbers of crash box segments used in this investigation are two segments, three segments with a sequence diameter and three segments with alternating diameter. The crash test components were impactor, crash box, and fixed rigid base. Impactor and the fixed base material are modelled as a rigid, and crash box material as bilinear isotropic hardening. Crash box length of 100 mm and frontal crash velocity of 16 km/jam are selected. Crash box material of Aluminum Alloy is used. Based on simulation results, it can be shown that three segments crash box with alternating diameter design has the largest crash energy absorption. From deformation pattern has showed that three segments crash box absorbs low energy at the beginning of crashing. Energy absorption start increased at the boundary area of the first, second and three segments as a result of increasing inertia where critical load has increased hence buckling phenomenon could be minimized.