Abstract
Currently, the most important structural design aims are weight reduction, corrosion resistance, high stiffness and vibration damping in several industrial applications, which can be provided by the application of advanced fiber-reinforced plastic (FRP) composites. The main research aim was to develop novel and innovative multicellular plate structures that utilize the benefits of lightweight advanced FRP and aluminum materials, as well as to combine the advantageous characteristics of cellular plates and sandwich structures. Two new multicellular plate structures were developed for the structural element of a transport vehicle. The first structure consists of carbon-fiber-reinforced plastic (CFRP) face sheets and pultruded glass-fiber-reinforced plastic (GFRP) stiffeners. The second structure consists of carbon-fiber-reinforced plastic face sheets and aluminum (Al) stiffeners. The second main goal of this research was the development of an optimization method of minimal weight for the newly developed all-FRP structure and the CFRP-Al structure, considering seven design constraints. The third main purpose was to confirm in a real case study that lightweight multicellular composite constructions, optimized by the flexible tolerance optimization method, provide significant weight saving (86%) compared to the all-steel structure. The added value of the research is that optimization methods were developed for the constructed new composite structures, which can be applied in applications where weight saving is the primary aim.