Investigating the Effect of Cement Grading on the Characteristics of Concrete and Standard Mortar

Grading is one of the most important characteristics of cement, which has a great impact on its performance in concrete. The most common methods of monitoring are determination of residues on sieves, Blaine and LD. In this study, introduce the main parameters of cement grading, optimal limits and its effects. Also 204 samples of Portland cement were prepared to determine their physical and mechanical properties and performance of Laboratory concrete mixtures. One of the most important results is the clear effect of increasing the share of 3 - 30 µ particles and cement uniformity coefficient on the compressive strength of concrete and mortar and providing relationships. The results of LD- PSD experiments were well correlated with the experiments remaining on the sieve by alpine method. With increasing uniformity or the amount of particles of 3 - 30 microns, the setting time of cement paste increases (becomes longer); which is not always desirable