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    Investigating the Influence of Waste Basalt Powder on Selected Properties of Cement Paste and Mortar
    (Iop Publishing Ltd, 2017) Dobiszewska, Magdalena; Beycioğlu, Ahmet
    Concrete is the most widely used man-made construction material in civil engineering applications. The consumption of cement and thus concrete, increases day by day along with the growth of urbanization and industrialization and due to new developments in construction technologies, population growing, increasing of living standard. Concrete production consumes much energy and large amounts of natural resources. It causes environmental, energy and economic losses. The most important material in concrete production is cement. Cement industry contributes to production of about 7% of all CO2 generated in the world. Every ton of cement production releases nearly one ton of CO2 to atmosphere. Thus the concrete and cement industry changes the environment appearance and influences it very much. Therefore, it has become very important for construction industry to focus on minimizing the environmental impact, reducing energy consumption and limiting CO2 emission. The need to meet these challenges has spurred an interest in the development of a blended Portland cement in which the amount of clinker is reduced and partially replaced with mineral additives - supplementary cementitious materials (SCMs). Many researchers have studied the possibility of using another mineral powder in mortar and concrete production. The addition of marble dust, basalt powder, granite or limestone powder positively affects some properties of cement mortar and concrete. This paper presents an experimental study on the properties of cement paste and mortar containing basalt powder. The basalt powder is a waste emerged from the preparation of aggregate used in asphalt mixture production. Previous studies have shown that analysed waste used as a fine aggregate replacement, has a beneficial effect on some properties of mortar and concrete, i.e. compressive strength, flexural strength and freeze resistance also. The present study shows the results of the research concerning the modification of cement paste and mortar with basalt powder. The modification consists in that the powder waste was added as partial replacement of cement. Four types of common cement were examined, i. e. CEM I, CEM II/A-S, CEM II/A-V and CEM II/B-V. The percentages of basalt powder in this research are 0%, 1%, 2%, 3%, 4%, 6%, 8% and 10% by mass. Results showed that the addition of basalt powder improved the strength of cement mortar. The use of mineral powder as the partial substitution of cement allows the effective management of industrial waste and improves some properties of cement mortar.
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    Mechanical properties of blended cements at elevated temperatures predicted using a fuzzy logic model
    (Techno-Press, 2017) Beycioğlu, Ahmet; Gültekin, Adil; Aruntaş, Hüseyin Yılmaz; Gencel, Osman; Dobiszewska, Magdalena; Brostow, Witold
    This study aimed to develop a Rule Based Mamdani Type Fuzzy Logic (RBMFL) model to predict the flexural strengths and compressive strengths of blended cements under elevated temperatures. Clinoptilolite was used as cement substitution material in the experimental stage. Substitution ratios in the cement mortar mix designs were selected as 0% (reference), 5%, 10%, 15% and 20%. The data used in the modeling process were obtained experimentally, after mortar specimens having reached the age of 90 days and exposed to 300 degrees C, 400 degrees C, 500 degrees C temperatures for 3 hours. In the RBMFL model, temperature (C degrees) and substitution ratio of clinoptilolite (%) were inputs while the compressive strengths and flexural strengths of mortars were outputs. Results were compared by using some statistical methods. Statistical comparison results showed that rule based Mamdani type fuzzy logic can be an alternative approach for the evaluation of the mechanical properties of concrete under elevated temperature.