As sand is an important construction material, it is always desirable to use the good quality sand. To judge the quality of the available sand, one must know the properties of good sand. Before using sand in a project, these desirable properties must be ensured.
Sand is a mixture of small grains of rock and granular materials which is mainly defined by size, being finer than gravel and coarser than silt. And ranging in size from 0.06 mm to 2 mm. Particles which are larger than 0.0078125 mm but smaller than 0.0625 mm are termed silt.
Properties of Good Sand
Followings are the desirable properties of sand:
- Should be completely inert. (i.e., should not have any chemical activity).
- Grains should be sharp, strong & angular.
- Should not contain any hygroscopic salts (i.e., CaCl2, MgCl2, etc.).
- Should not contain clay & silt; usually 3-4% clay & silt is ordinarily permitted for practical reasons.
- There should be no organic matter.