Sürdürülebilir Kalkınma Amaçları

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• MakaleAçık Erişim2021/r/gumushane/16761
  The investigation of mechanical properties of polypropylene fiber-reinforced composites produced with the use of alternative wastes

  Külekçi, Gokhan; Çullu, Mustafa

  Various studies on the disposal or storage of the wastes generated due to mining activities have been carried out until today. With the developing technology, the use of alternative products instead of aggregates in Composite and the effect of fiber addition were investigated. The most common of these studies is the bending strength tests on the beam sample. In this study, solid wastes generated by mining operations were used instead of aggregate used in Composite. Beam samples were poured with the dimensions of 40x40x160 mm by adding 4-6 kg/m(3) polypropylene fiber to the mixture obtained by using these solid wastes; then, its effects on ultrasonic pulse velocity test, tensile test, and compressive strength tests were conducted. According to the results of these tests, it was found that the fibers had a positive effect on compressive strength and bending strength. Also, it was found that water absorption rates and densities did not have an effect, while the ultrasonic pulse velocity decreased with increasing fiber content.

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• MakaleYalnız künye2021/r/gumushane/16734
  Investigation of fly ash added light concretes with respect to gamma radiation transmission properties of 133Ba and 137Cs

  Külekçi, Gokhan

  With the help of the developing concrete technology, light concrete and fly ash may be used in several concrete-related fields. To provide protection from radiation, which is one of the current problems of the world, several researchers have used fly ash, but very few researchers have worked on light concrete. To be protected from the effects of radiation, researchers have examined gamma radiation absorption properties by using heavy concrete and heavy aggregates. In this study, by using Class C fly ash at the doses of 30-50-100% instead of cement, three different light concretes were prepared. Density and compressive strength experiments were conducted on the composite blocks prepared with dimensions of 50*50*50 mm, and linear absorption coefficients (cm(-1)), mass attenuation coefficients (MAC) and Tenth value layer (TVL) radiation interaction parameters were measured. Radiation interaction parameters were obtained using an HP Ge gamma detector. For radiation measurements, four different photon energies as 583 keV (Ba-133), 609 keV (Ba-133), 661 keV (Cs-137) and 911 keV (Ba-133) were used. As a result of the analyses, it was determined that compressive strength decreased as the fly ash content increased, the lowest compressive strength values were obtained in the samples containing 100% fly ash among the prepared composites, and density increased as the fly ash content decreased. It was observed that, in the prepared composites, as the energy levels increased, the linear absorption coefficients also increased, and the samples containing 30% fly ash provided the best TVL value on the energy level of 911 keV. With this study, it was revealed that fly ashes that are used in many fields could be used as a radiation shield. Additionally, with this study, due to not using heavy aggregates and due to the production of light concrete in the production of radiation shields, the cost of shield production will significantly decrease.

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