Function of Sand in Mortar
Followings are the functions of sand as one of the ingredients of mortar.
- Generally, sand is not used in mortar to increase its strength. Rather it is mainly used as an inert material to increase the volume of mortar for the economy.
- Using sand in the right amount can produce cheap mortar without hampering mortar strength.
- Sand subdivides the paste of cementing materials into a thin film which is the basic principle involved in using all cementing materials.
- Sand offers the requisite surface area for the film of cementing materials to adhere and to spread.
- Sand helps to prevent mortar shrinkage. It also prevents cracking of mortar during setting.
- Well-graded sand increases the density of mortar.
- Sand allows Carbon-Di-oxide from the atmosphere to reach to some depth in case of ft lime mortars and thereby improves their setting capability.
- It is also claimed that some chemical reaction takes place between silica (SiO2) of sand grains and the constituents of the cementing materials to form a hardened mass.
- A text Book of Engineering Materials by Dr. M.A. Aziz