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One of the essential requirements in modern civil engineering is a sustainable building, with the aim of reducing the harmful impact on the environment. Since the early XXI century, usage of recycled materials has been insisted on, which could, at least partly, substitute traditionally used materials. Although there is no serial manufacturing of TV sets with cathode ray tubes anymore, piles of cathode ray tube glass (CRT) at the waste disposal sites have still been on the increase. This experimental research was supposed to determine the potential for using subtly milled CRT glass as a supplementary cementitious material and to check the resistance of similar concretes to the sulphate action. Six testing concrete batches were made. The percentage of cement replacement percentage with CRT was: 5%, 10%, 15%, 20% and 35%, by mass. Durability assessment of concrete to sulphate action was done by visual estimation of concrete appearance as well as through testing the compressive strength variations of treated concrete specimens 3, 6, 12 and 36 months old. After soaking the specimens in a 5% solution of Na2SO4 for 36 months, concretes with 15% to 20% of replaced cement with finely ground CRT glass have simultaneously satisfactory compressive strength and resistance to sulfate attack. In this sense, this range of replacement of cement with finely ground CRT glass can be recommended for practical application. [ABSTRACT FROM AUTHOR]

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Rapid technological and industrial development in the recent decades caused considerable environmental problems, and one of the most significant is, undoubtedly, disposal and recycling of waste materials and by-products of industrial production. Since concrete is a composite material, waste materials can suitably be used in its composition. In this paper, the research of effects of milled recycled glass from cathode tubes, flotation tailings from a copper mine, red mud and fly ash as mineral admixtures on properties of fresh and hardened self compacting concrete was presented. The test results indicated that the addition of such materials does not cause a decline in physico-mechanical characteristics and properties of durability of self-compacting concretes (SCC), and they even improve some aspects of concrete performance in comparison with SCC made with limestone filler as mineral admixture. Waste materials such as fly ash and recycled glass of cathode tubes (CRT) exhibit a puzzolanic activity, so the performances of the concretes with these admixtures proved to be better after ageing than the concretes with other admixtures. [ABSTRACT FROM AUTHOR]

Rapid technological and industrial development in the recent decades caused considerable environmental problems, and one of the most significant is, undoubtedly, disposal and recycling of waste materials and by-products of industrial production. Since concrete is a composite material, waste materials can suitably be used in its composition. In this paper, the research of effects of milled recycled glass from cathode tubes, flotation tailings from a copper mine, red mud and fly ash as mineral admixtures on properties of fresh and hardened self compacting concrete was presented. The test results indicated that the addition of such materials does not cause a decline in physico-mechanical characteristics and properties of durability of self-compacting concretes (SCC), and they even improve some aspects of concrete performance in comparison with SCC made with limestone filler as mineral admixture. Waste materials such as fly ash and recycled glass of cathode tubes (CRT) exhibit a puzzolanic activity, so the performances of the concretes with these admixtures proved to be better after ageing than the concretes with other admixtures. [ABSTRACT FROM AUTHOR]

This paper presents the testing of the durability of concrete where a part of cement was replaced with ground panel cathode ray tube glass (CRT) finer than 63 µm. The percentage of cement replaced with glass is 5%, 10%, 15%, 20%, and 35%, by mass. The highest percent share of mineral admixtures in CEM II (Portland-composiste cement) cement was chosen as the top limit of replacement of cement with glass. In terms of the concrete durability, the following tests are performed: freeze-thaw resistance, freeze-thaw resistance with de-icing salts-scaling, resistance to wear according to the Böhme test, sulfate attack resistance, and resistance to penetration of water under pressure. A compressive strength test is performed, and shrinkage of concrete is monitored. In order to determine the microstructure of concrete, SEM (Scanning Electron Microscopy) and EDS (Energy Dispersive X-ray Spectroscopy) analyses were performed. The obtained research results indicate that the replacement of a part of cement with finely ground CRT glass up to 15% by mass has a positive effect on the compressive strength of concrete in terms of its increase without compromising the durability of concrete. The results obtained by experimental testing unequivocally show that concrete mixtures made with partial replacement (up to 15%) of cement with finely ground CRT glass have the same freeze-thaw resistance, resistance to freeze/thaw with de-icing salt, resistance to wear by abrasion, and resistance to sulfate attack as the reference concrete. In terms of environmental protection, the use of CRT glass as a component for making concrete is also very significant. [ABSTRACT FROM AUTHOR]