Bending Deep Collapse Of Automotive Type Components

Development of a systematic computer method to determine the energy absorption in a general collapse mechanism is the main objective of this paper. Models of several collapse modes have been developed to estimate the amount of energy absorbed in an automobile body structure during collision. These models will aid design of structural components for crash energy management and facilitate sensitivity studies to check the robustness of alternate concepts.

Bending strengths and collapse modes of vehicle structural members are presented. Mathematical models based on the section collapse mechanism are developed. The shape of collapse mechanism shows to play a significant role in determining the energy absorption during automobile collision. A strip method approach is used, in which the cross-section under consideration is divided into a number of plate sub-elements (“strips”). The system finds the stresses in each strip and identifies the sub-element which initiates buckling. The shape of collapse mechanism, the yield lines and the angles of rotation for each sub-element are then determined. A relationship between the hinge moment and rotation can thus be obtained. This method can be applied to a general-shaped component of a thin- or thick-walled automotive type section composed of plate type (strip) elements. The computer results show good agreement with the actual tests.