The Effects of Spot Weld Pitch to the Axial Crushing Characteristics of Top-Hat Crash Box

Abstract

Numerical study of the effect of spot weld pitch with respect to top-hat crash box crushing characteristics are presented in this paper. Belytschko-Lin-Tsay shell element was used for modeled columns wall with Piecewise Linear Plasticity material model. The impactor was modeled using hexahedral solid elements and assumed as a rigid body. Spot weld joints used to connect mild steel St37 plates of the columns were modeled using beam element and solid element. Impact characteristics related to the spot weld pitch and models were evaluated from simulation results in the form of crushing force vs axial deformation of the column. The results show that spot weld pitch does not significantly affect the crushing characteristics for top-hat crash box with beam element spot weld model, while solid element spot weld model show otherwise. The difference between beam element spot weld model and solid element spot weld model is larger at spot weld pitch 0.50H – H, and tend to close at higher spot weld pitch. Top-hat crash box model becomes stiffer with solid element applied as spot weld model.