Performance analysis and optimization of square tubes with different shapes, sizes, and patterns of holes under axial compression loading

Abstract

Tubular structures are common in vehicles in the form of crash energy absorbers. Inevitably, these tubes contain holes for assembling fasteners and heating sources. Though the introduction of holes in the surface of the tube minimizes the initial peak crushing force (IPF), their structural stability also gets affected, which leads to a reduction in energy absorption capacity (EA). Therefore, the shape, dimension, and patterns of the holes in the tubular structure are to be scrutinized to minimize its unstable response during the crash event. This paper addresses the hole’s position, shape, and dimensional effects on the performance characteristics of aluminum square tubes subjected to axial quasi-static compression experimentally. Numerical models were initially created using ABAQUS/CAE® code for simulating the quasi-static structural response of square tubes (without holes) and validated against experiments. Further, numerical analysis was explored to investigate the hole’s position, shape, and dimensional effects on IPF and EA. The performance characteristics of all the examined specimens were quantified based on the best performance with the help of the TOPSIS method. Finally, Response Surface Methodology (RSM) was carried out to determine the best optimal square tube with holes. It was observed that, with an increase in the hole size, the IPF gets minimized. Among all the specimens, the diamond-shaped hole exhibits the best performance characteristics. The study also reveals that the EA varied greatly with the arrangement of holes (patterns). The research findings can provide ample guidance when designing crash tubes in the automotive protective system.

Keywords:

• Axial compression
• crashworthiness
• decision making
• energy absorption
• optimization
• square tubes

Disclosure statement

No potential conflict of interest was reported by the author(s).