In this study, effects of adding limestone powder on mechanical characteristics of concrete are surveyed. Objective of this research is to study interactive effects of water-cement & powder-cement ratios on compressive strength, tensile strength and modulus of elasticity of concrete at the ages of 7, 28 and 90 days. The used samples in the experiment were made using different values of cement and powder. The performed elementary experiments in this research showed that substitution of limestone powder by fine and coarse aggregate in concrete simultaneously, has the good improvement on mechanical characteristics of concrete. The results of experiments showed that addition of limestone powder to concrete has variative effects on mechanical characteristics of concrete and in high values of water-cement ratios, increasing compressive strength of concrete can be expected by adding powder to concrete.
)