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This research paper presents the use of wasteful supplementary cementitious materials like fly ash and silica fume to conserve the cement used in concrete. The cement industry is one of the major producers of greenhouse gases and an energy user. In this study, Portland cement was used as a basic cementitious material. Fly ash and silica fume were used as the cement replacements by weight. The replacement levels of fly ash were 30%, 40% and 50%, and silica fume were 6% and 10%. The water binder ratio was kept constant as 0.4 and super plasticizer was added based on the required workability. Results of the binary and ternary concrete mixtures compressive strength, split tensile strength and flexural tensile strength were taken for studyup to 90 days. Based on the experimental results of compressive strength, prediction models were developed using regression analysis and coefficients were proposed to find the split tensile strength and flexural strength of binary-ternary concrete mixtures at 28 and 90 days.

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The present study focuses on measuring the effects of industrial wastewater disposed from thermal electricity power plant as by-product on the geotechnical properties of sandy soil and applying washing process to remediate the contaminated soil samples and measure the efficiency of washing technique. The disturbed sandy soil samples were obtained from Al-Kufa City located to the southwest of Iraq and the industrial wastewater obtained from Al-Musayib thermal electricity power plant. The intact sandy soil was contaminated in the laboratory with four percentages of industrial wastewater (10, 20, 40 and 100%) calculated according to the weight of dry soil. The industrial wastewater is mixed with distilled water to constitute the solution used in the contamination process of soil through soaking the soil by this solution for 30 days. The study results showed that with increasing the percentages of the contaminant, there was a slight increase in both the liquid limit and particle size, while there was a significant increase in the optimum water content. Nevertheless, a slight decrease was observed in the specific gravity, maximum dry unit weight, and void ratio, while, a considerable decrease was noticed in the angle of the internal friction and coefficient of permeability of soil. The proposed remediation technique “soil washing” is efficient, economical, and time saving when used to remediate sandy soils. After remediation, the results showed an increase in the cohesion, angle of internal friction and maximum dry unit weight. Also, a slight increase was observed in the specific gravity, void ratio and permeability coefficient of remediated soil samples when compared with that of contaminated samples. The removal efficiencies of contaminant from soil were (97.63, 96.79, 96.58, and 93.87%) for the soil samples contaminated with industrial wastewater by (10, 20, 40 and 100%), respectively.