دانلود رایگان مقاله تقویت پر کننده دستگاه های جذب انرژی فوم پر با پرتوهای CFRP

Abstract

The crashworthiness of fiber reinforced plastics (FRP) is attracting more interest as they are currently contributing to several industries. In the present study, internally strengthened foam-filled rectangular carbon fiber reinforced plastics (CFRP) composites are presented for energy absorption applications. Commercially available carbon/epoxy beams/tubes were employed. After arranging the internal strengthening, each structure was filled with foam for better structural integrity. The structures were subjected to lateral compression and their crashworthiness was assessed using the peak load, the mean crushing load, the stability during post-crushing, the energy absorption, and the specific energy absorption. Up to 100% improvement was observed in both the energy absorbed and the load carrying capacity (refereeing to the peak load and the mean crushing load). Moreover, the stability in the post-crushing stage did not show significant dependency on the strengthening arrangement. Since it is highly dependent on the specimen weight, which is different from one specimen to another, the specific energy absorption showed different responses compared to the scalar value of the energy. For some configurations, internal strengthening had a negative effect on the specific energy. In contrast, an improvement of up to 22.5% was achieved for the other specimen configurations.

5. Conclusions

An experimental optimization study was implemented in this research to investigate the effect of internal strengthening of foam-filled 2 4 rectangular tubes made of CFRP. Six different strengthening schemes were adopted in addition to the original baseline configuration. The internal strengthening was carried out by fabricating different cross-sections using 1 2 rectangles, hats, and I-beams made of CFRP. The manufacturing sequence started with arranging and gluing the strengthening inside the 2 4 rectangular tubes and then pouring in the two-part foam system. The proposed configurations were subjected to compression loading up to final densification at a test speed of 15 mm/min. The results showed that any strengthening with the proposed methodology advantageous to the load carrying capacity. A minimum improvement of 13% was achieved for configuration D (with two hats and two I-beams) in the peak load. An improvement of up to 100% was observed for configuration E (four hat beams) in the peak load. Similarly, the improvement in the mean crushing load reached 100% for configuration F specimens. The stability of the crushing process, as measured by the CFE and CLS, did not show a clear improvement, as the load-displacement plot did not exhibit stable crushing. The energy absorption (E) showed significant improvement (up to 100%) for some strengthening arrangements. All of the proposed arrangements resulted in improvement in the quantity of the energy absorbed. For the normalized energy ES, some of the configurations showed improvements of 22.5%. In contrast, for configurations B, C, and F, there were no recorded improvements in the specific energy absorbed, which reveals that the improvement in the energy (E) was due to the increase in the specimen weight.