Crashworthiness and technoeconomic assessment of bioinspired GFRP PP tubes using experiments numerical modeling and artificial neural networks

This study presents a comprehensive experimental and computational investigation of the quasi-static axial compression behavior of glass fiber-reinforced polymer/ polypropylene (GFRP/PP) sandwich tubes inspired by bamboo and horsetail structures, designed for crashworthiness applications. The combination of these materials, due to their high strength-to-weight ratio, offers excellent energy absorption capabilities. To this end, firstly, single-hollow tubes were investigated numerically and experimentally. After ensuring the accuracy of the numerical results, many numerical sandwich tubes were simulated to investigate the effect of geometric parameters. Then, the numerical results such as peak crushing force (PCF) and specific energy absorption (SEA) were used as input data for learning of multi layers perceptron (MLP) algorithm network. Finally, using genetic algorithm showed the optimal specimen with t = 1.2 mm, h = 80 mm, and 3 GFRP sub-core tubes has the optimal crashworthiness performance. This specimen exhibits the optimal PCF (18.24 kN) and SEA (7.8 J/g) values compared with the other samples. In addition, a techno-economic assessment was conducted using the Net Present Value (NPV) method to determine the long-term financial viability of replacing traditional materials with GFRP/PP. This approach is an essential step in bridging the gap between technical performance and industrial applicability. The results revealed that while GFRP/PP crash tubes offer superior weight-specific energy absorption, their economic competitiveness varies by reference material. Specifically, replacing steel and aluminum crash boxes with GFRP/PP results in positive net present values of $322.49 and $240.27 per vehicle, respectively, highlighting clear financial and environmental benefits.