Natural or River sand are weathered and worn out particles of rocks and are of various grades or sizes depending upon the amount of wearing. Now-a-days good sand is not readily available, it is transported from a long distance. Those resources are also exhausting very rapidly. So it is a need of the time to find some substitute to natural river sand. The artificial sand produced by proper machines can be a better substitute to river sand. The sand must be of proper gradation (it should have particles from 0.075 mm to 4.75 mm in proper proportion). When fine particles are in proper proportion, the sand will have fewer voids. The cement quantity required will be less. Such sand will be more economical. Demand for manufactured fine aggregates for making concrete is increasing day by day as river sand cannot meet the rising demand of construction sector. Natural river sand takes millions of years to form and is not repleneshible. Because of its limited supply, the cost of Natural River sand has sky rocketed and its consistent supply cannot be guaranteed. Under this circumstances use of manufactured sand becomes inevitable. River sand in many parts of the country is not graded properly and has excessive silt and organic impurities and these can be detrimental to durability of steel in concrete whereas manufactured sand has no silt or organic impurities.

Looking at the current scenario and above stated facts, Greensand Industries have ventured into manufacturing of the following sands as per IS Specifications.

• The manufactured sand has required gradation of fines, physical properties such as shape, smooth surface textures and consistency which makes it the best sand suitable for construction. These physical properties of sand provide greater strength to the concrete by reducing voids and capillary. Thus required grade of sand for the given purpose helps the concrete fill voids between coarse aggregates and makes concrete more compact and dense, thus increasing the strength of concrete.

• This type of sand is mainly used for masonry or Tile-laying works. This size falls in between the concrete and plastering M Sand thus reducing the Mortar space between the bricks and also avoiding voids
  

• Plastering Sand is a fine textured sand that is primarily used for both internal and external rendering applications providing a smooth finish.
• This type of sand is carefully manufactured in a process so as to minimize the silt content thus reducing the risk of shrinkage and eliminating the cracks
• Suitable for use in a wide range of applications, plastering sand is not as coarse as concrete sand. It is often used for the plastering of wall and is used in laying of tiles and stones

uses

• Roads
• Ready Mix Mortar
• Constructions
• Pre mix concrete
• Pre Cast Concrete






Property	River sand	Manufactured sand	Remarks
Shape	Spherical particle	Cubical particle	Good
Gradation	Cannot be controlled	Can be controlled
Particle passing 75micron	Presence of silt shall be less than 3%(IS:383-1970)reaffirmed 2007	Presence of dust particle shall be less than 15%	Limit 3% for uncrushed & limit 15% for crushed sand
Silt and Organic impurities	Present (Retard the setting & Compressive Strength)	Absent	Limit of 5% for Uncrushed & 2% for Crushed sand
Specific gravity	2.3 – 2.7	2.5 – 2.9	May vary
Water absorption	1.5 - 3%	2 – 4%	Limit 2%
Ability to hold surface moisture	Up-to 7%	Up-to 10%
Grading zone(FM)	Zone II and III FM 2.2 -2.8	Zone II FM 2.6 – 3.0	Recommends Zone II for Mass Concrete
Soundness (Sodium sulphate-ss & Magnesium sulphate -ms) (5 cycles)	Relatively less sound (Ex. >5)	Relatively sound (Ex. <5)	Limit 10% ss and 15% ms
Alkali Silica Reactivity	0.002 -0.01	0.001- 0.008	Limit 0.1%expansion
Workability & its retention	Good & Good retention	Less & Less retention	Control of fines & apply water absorption correction, use of plasticisers
Setting	Normal	Comparatively faster	Apply water absorption correction, use retarders
Compressive strength	Normal	Marginally higher	As shown above
Permeability	Poor	Very poor
Cracks	Nil	Tend to surface crack	Early curing & protection of fresh concrete