The wastes from polyethylene terephthalate (PET) packaging can be turned into armatures for concrete used in the transports infrastructure (roads with rigid concrete structure, pedestrian and concrete pavements and borders), as well as in the construction of safety elements (support walls, bulwark foundations). This experimental research was meant to create dispersed reinforced concrete with armatures from polyethylene waste, originated from the recycling programmes of PET-type packaging. The experimental programme was aimed at constructing some samples of dispersed reinforced concrete from recycled material coming from polyethylene terephthalate (PET) packaging wastes, their testing to the compressive strength and the comparison of results with the characteristics of the standardised samples of concrete (class C30/37). All the reinforcements used in this work to consolidate the dispersed reinforced concrete type were made from a mix of polyethylene terephthalate (PET) packages, of different types and characteristics, which are found daily in supermarkets and which then reach waste. The choice of a mix of polyethylene terephthalate (PET) packaging was chosen in order to render the general recycling of these types of materials as good as possible.

The cavitation erosion resistance of an X5CrNi18-10 stainless steel, solution treated at temperatures in the range of 1000–1100 °C for 5–50 mins, was investigated using a piezoceramic vibrating system. The variation of the technological parameters led to changes in the degree of the chemical homogeneity and the grain size of the austenite. Heating at 1050 °C for 25 mins, followed by water quenching, led to an increase in the cavitation erosion resistance of about 2.45 times compared to the samples heated for 50 mins. A significant improvement of the cavitation resistance was obtained for the sample maintained at 1050 °C compared to the samples annealed at 1000 and 1100 °C. It was found that the associated cavitation erosion resistance is improved for finer granulation and for higher degree of chemical homogeneity of the austenite.

The recent development in enhancing the corrosion resistance of materials by covering with powdered layers open the way to use the procedure also for cavitation erosion protection, phenomenon always present in hydraulic machinery runners as well as ship propellers. The present research analyzes the behavior of four different types copper layers, deposited with high velocity flames, HVOF upon specimens realized from cast steel for general use 270-480 W (equivalent with OT500-3 used in Romania), to cavitation erosion in a Laboratory device. Even if the powder density and the layers thickness have close values, the behavior to cavitation erosion is different and depend primarily on the powder chemical composition and the microscopic structure.

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Woven fiber reinforced concrete is a material, which contains various quantities of polymer materials in composition, in addition to the conventional components of an ordinary concrete (mineral binder - cement, aggregates, water and additives). The present work refers to the concrete in which the reinforcement is made of polymeric materials (polyethylene terephthalate), originated from the recycling programs of PET-type packaging. The experimental program was aimed at constructing some samples of woven fiber reinforced concrete from recycled material coming from PET packaging wastes, their testing to the compression demands and the comparison of results with the characteristics of the standardized samples of concrete (class C30/37). Based on a sufficient number of determinations, certain correlations can be established between the compressive strength of the concrete at 28 days depending on the dosage of components (aggregate, binder, and reinforcement), water / cement ratio, reinforcement volume, etc., essential parameters from a compositional point of view. These correlations, customized by cement type and strength class, are very important to determine - with approximation - to what dosage of components (aggregate, binder, reinforcement) the respective level of compressive strength of concrete is obtained.