El-Cezeri Journal of Science and Engineering, vol.10, no.1, pp.90-98, 2023 (Scopus)
Concrete quality is affected by many factors such as mixing ratios, material quality, transporting, placing and curing. One of the crucial factors that changes the compressive strength of concrete is aggregate which makes up 75% of concrete during concrete production. Properties of aggregate are more unstable than other materials depending on various reasons. Granulometry, moisture or organic substance amount of the aggregates which have same origin may differ within time. This study investigates physical and mechanical properties of crushed limestone and crushed river aggregates. It is on optimum design of concrete with crushed limestone and crushed river aggregates. At first, physical and mechanical properties of the aggregates are measured, then Taguchi method is applied. Test variables are water-to-binder ratio, cement dosage, river sand ratio to limestone and air entrained agent. L16 orthogonal array as an experimental design method is applied to determine the optimum concrete design in terms of compressive strength and flexural strength. Furthermore, contribution of variables on compressive and flexure strength is determined statically by using ANOVA method. Among the 4 different aggregate ratios evaluated in the study, the best performance is from the combination of 70% stream and 30% limestone. The weakest performance is from the series that do not contain any stream material.