Crashworthiness of a crisscross-reinforced square honeycomb under out-of-plane crashing

Abstract

In this article, the crashworthiness of a crisscross-reinforced square honeycomb under out-of-plane crashing was investigated theoretically and numerically. The square honeycomb is formed by the improved crisscrosses. The webs of the crisscross have variable thickness and unequal section length, which make the property of the honeycomb improved. An explicit formulation was deduced for predicting the mean crushing force. A finite element method based numerical analysis model was built to calculate the crashworthiness, and a surrogate model based multi-objective optimisation model was set up for designing the cross-sectional parameters including the thickness and the section lengths of webs. The theoretical prediction results have a good agreement with the numerical results, and the prediction formulation was further modified by the numerical results. The theoretical and numerical results showed the thickness of the crisscross webs greatly affect the crashworthiness. A square honeycomb with high specific energy absorption and low peak crushing force was obtained through optimising the cross-sectional parameters of the honeycomb. The specific energy absorption increases about 70% and the peak crushing force drop over 40% after the optimisation.

Keywords:

• Crisscross-improved square honeycomb
• out-of-plane crashing
• crashworthiness
• theoretical prediction
• design optimisation

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors acknowledge the support of the National Natural Science Foundation of China (Grant nos. U1808215, 11572073 and 11821202), the 111 Project (B14013), and the Fundamental Research Funds for the Central Universities of China (DUT19GF102).