M - 60
The Artificial Sand Produced by Proper Machines Can Be a Better Substitute to River Sand. The Sand Should Be Sharp, Clean and Course. The Grains Should Be of Durable Material. The Grain Sizes Must Be Such That It Should Give Minimum Voids. The Presence of Clay and Silt Retards the Setting of the Ce- ment and Makes the Mortar Weaker and the Walls or the Slab Leaks and Holds Dampness.
The Sand in the Mortar Does Not Add Any Strength but It Is Used as an Adulterant for Economy and With the Same It Prevents the Shrinkage and Cracking of Mortar in Setting. The Sand Must Be of Proper Gradation (It Should Have Particles From 150 Microns to 4.75 Mm in Proper Proportion) When Fine Par- ticles Are in Proper Proportion, the Sand Will Have Less Voids. The Cement Required Will Be Less When There Will Be Less Void in Sand. Such Sand Will Be More Economical.