Materials, Methods & Technologies, Volume 9, 2015

Abstract: In the present study, the effects of the cements formed by substituting Portland Cement (PC) with different ratios of blast furnace slag and waste tire rubber powder on initial and final setting times are investigated. To this purpose, Portland cement replaced with blast furnace slag as a ratio of its weight of 0, 5, 10, 15 and 20%, waste tire rubber powder as a ratio of its weight of 0, 2.5, 5%, both blast furnace slag and waste tire rubber powder as a ratio of its weight of 2.5+2.5%, 7.5+2.5%, 5+5%, 10+5% and 15+5%. By this procedure, twelve different mixtures were prepared and effect of cement was investigated on the initial and final setting time. According to the results obtained in the initial and final setting times all the mixing ratio of the prolonged period of time was determined. Also, by using Fuzzy Logic method, prediction model was formed based on the quantity of blast furnace slag and waste tire rubber powder to predict the initial and final setting times of cement. The experimental results are compared with the fuzzy logic results and the correlation coefficients for the initial and final setting time are found 0.93 and 0.95, respectively. These results show that the developed model can be successfully applied in the cement and concrete industry.