PSI - Issue 28

Boris N. Fedulov et al. / Procedia Structural Integrity 28 (2020) 155–161 Fedulov B., Fedorenko A., Jurgenson S., Kantor M., Lomakin E. / Structural Integrity Procedia 00 (2019) 000–000

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Fig. 7 shows loading curves for numerical tests performed for conventional plate and for two plates with proposed technique of reinforcements. First proposed plate has an equivalent metal consumption 170 kg per m 3 with conventional plate, and as a result, it has double bending stiffness and strength. Second plate based on metamaterial enforcements has approximately two times less weight of metal material and has the same stiffness and strength characteristics as conventional plate.

Fig. 7. Loading curves for conventional and proposed plates.

4. Discussion This type of metamaterial based on pyramid support intermediate layer made of classical metal alloy now days takes essentially reasonable efforts for fabrication. It can be produced by means of few steps: laser cutting, stamping and laser welding. Alternatively, even by means of bending of metal stripes and welding only. This structure has a list of remarkable features. The weight and optimum transfer loads through the set of proposed stiffeners. This type of plate usually gets failure or any load onset due to buckling of “pyramid edge” bars, which almost impossible because surrounding concreate supports them and prevent from buckling. Next feature – is durability, failure of one cell of the material never causes failure of entire structure, it makes load to get a redistribution with a small increase of stresses in the rest of elements of construction. 5. Conclusions The design of construction slab based on three layer metamaterial has been proposed. The idea of geometry shape for internal enforcements was taken from the topology optimization algorithm. Three point bending numerical experiment up to failure has been performed with different construction plates. It has been shown that stiffness and strength characteristics two times higher in comparison with conventional plate with metal bars enforcements under condition of equivalent metal consumption. Acknowledgements This research supported by RFBR Grant number 18-31-20026 and 20-01-00356