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Copyright of Proceedings on Quality is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The strength development of concrete containing ground granulated blast-furnace slag (GGBS), a by-product of iron in blast-furnace, as a partial substitute for cement, was experimentally studied. Levels of replacement of cement by slag were 12.5 %, 25 %, 37.5 %, and 50 % by weight of cement. Slag taken immediately after it was discharged from the blast furnace was used. Tests performed on concrete samples include consistency, air content, compressive strength, flexural strength, and dynamic modulus of elasticity. It was found that the addition of GGBSleads to a significant increase in the consistency of fresh concrete, a decrease in early compressive strengths and flexural strengths, as well as dynamic modulus of elasticity. At a later age, the replacement of cement with slag resulted in increasing both the modulus and strength of concrete. [ABSTRACT FROM AUTHOR]

This paper examines the possibility of producing metallurgical cement type CEM III/A 42.5N at the Kakanj Cement Factory. The tested samples contain respectively 46%, 41%, and 38% of granulated blast furnace slag and the rest is clinker. According to the test results, all cement samples meet the EN 197-1 standard in terms of physical-mechanical properties both after the initial period (2 days) and after the final period (28 days). As a result of the conducted tests, it can be concluded that the production of metallurgical cement type CEM III/A 42.5N at the Kakanj cement factory is possible and that its production would provide a number of ecological and economic benefits. [ABSTRACT FROM AUTHOR]

Two clays from deposits located in the region of Central Bosnia, and kaolin obtained from a local spark plug and technical ceramics factory were calcined at 800, 900, and 1000 °C. The pozzolanic activity of calcined raw materials was determined using the P test. Calcined clay from the deposit Bilalovac showed slightly better reactivity compared to calcined clay from the deposit Klokoti, and in both clays, the reactivity increased with increasing calcination temperature. Calcined kaolin was more reactive than clays and the highest reactivity was achieved when calcined at 800 °C. The strengths of mortars in which 20 % of cement was replaced with calcined raw materials showed the same trend of behavior as in the P test. Partial replacement of cement with calcined clays lead to a slight decrease in the strength of cement mortar, and the best results were obtained with clays calcined at 1000 °C. [ABSTRACT FROM AUTHOR]

Copyright of Proceedings on Quality is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents an experimental investigation into the effect of nanosilica addition to porosity and capillary absorption of concrete. Three concrete mixtures 0%, 2%, and 4% nanosilicaby weight of cementweretested. The procedure described in ASTM C642-06 was used to determine the total volume of permeable voids. Water absorption and the rate of water absorption (sorptivity) was tested in accordance with ASTM C1585-13. The initial and secondary rate of absorption was calculated for each mix. Also, concrete compressive strength at 28 days was determined. Testresults indicated that the incorporation of nanosilicainconcrete resulted inadecreased volume of permeable voids, total water absorption and rate of water absorption, and increased compressive strength at 28 days. [ABSTRACT FROM AUTHOR]

Particle size distribution measurements were performed on ground granulated blastfurnace slag by laser diffraction with the powder dispersed in distilled water with sodium hexametaphosphate used as dispersing agent, as well as in pure distilled water and propan-2-ol. Two samples of slag with Blaine fineness 4700 cm²/g and5500 cm²/g were tested. The results showed significant differences between results obtained by using different dispersants. Percentiles dv10 and dv50 are significantly lower when propan-2-ol or pure water were used instead of water with SHMP as dispersing agent. [ABSTRACT FROM AUTHOR]

The paper examined the changes in properties of conventional castables composed of a mixture of calcium-aluminate cement and chamotte caused by changes in the particle size distribution. Properties of castable with 20 % cement and „as received" chamotte were compared with castableofparticle size distribution adapted to the calculated distribution using the Andreasen equation. Porosity, water absorption, density and strength of samplesafter three-day curing and samples fired at 1100 °C were examined. It was found that samples with adjustedparticle size distribution gave better results than those prepared with „as received" particle size distribution, especially regarding strength. [ABSTRACT FROM AUTHOR]

The physical-mechanical properties of concrete with nanosilica were experimentally studied. Nanosilica in powder form was used as a partial replacement of cement at dosage of 3 and 6 wt.%. The experimental results show that the compressive strengths of concretes with nanosilica particles were all higher than those of reference concretes at ages 1, 7, 28 and 90 days. Also, at age of 28 days flexural strength, dynamic modulus of elasticity and apparent density have been increased, while water absorption has been decreased. [ABSTRACT FROM AUTHOR]

The paper examined the conventional castables composed of a mixture of high aluminate cement with 70% Al2O3, chamotte waste with 42% Al2O3 and brick clay „Rapajlo“. The influence of particle size distribution on density, porosity, water absorption, modulus of rapture and cold crashing strength was investigated. Particle size distribution was determined by the Dinger and Funk equation, using four different coefficient q. With the reduction of coefficient q, the amount of fine fractions is increased and the amount of larger fractions is decreased. Two series of samples were investigated. In the first series as the smallest fraction of all mixtures with different factor q was used high aluminate cement and water-cement ratio 0.485. Increasing the amount of cement has led to increasing the density and strength of castable. The increased amount of water has led to an increase in porosity. In the second series, the amount of cement and water remained the same, a part of the superfine fraction is replaced by clay. Replacing chamotte waste with clay leads to a slight increase in the density and strength of the material. When a part of the cement is also replaced with clay it slight reduce the density and strength of the material, because part of the water is placed between sheets of clay minerals and leads to an increase in volume, and at the same time reducing the amount of water needed for the reaction with cement. [ABSTRACT FROM AUTHOR]

Copyright of Proceedings on Metallic & Nonmetallic Materials is the property of University of Zenica, Faculty of Metallurgy & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Metallic & Nonmetallic Materials is the property of University of Zenica, Faculty of Metallurgy & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Metallic & Nonmetallic Materials is the property of University of Zenica, Faculty of Metallurgy & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Metallic & Nonmetallic Materials is the property of University of Zenica, Faculty of Metallurgy & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Metallic & Nonmetallic Materials is the property of University of Zenica, Faculty of Metallurgy & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Metallic & Nonmetallic Materials is the property of University of Zenica, Faculty of Metallurgy & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)