SAND FOR CONCRETE

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Sand as fine aggregates is the one of the main ingredients of concrete, the characteristics of sand also affects either strength or durability of concrete produced.

THE CHARACTERISTICS OF GOOD SAND FOR CONCRETE MIXING
The following are the properties of good sand for concrete preparation required for construction
  • Clean sand free from dust  
The sand should free from dust and other fines which could add the amount of water required for concrete, which reduce the work-ability of the concrete.
The dust between sand particles reduce the bond between particles and increases the amount of cement required for mixing and make the concrete uneconomical.
  • Inert sand
The sand should not contain any reactive substances and salts such as sulfur, sulfates, nitrate and also should be nonreactive towards chemicals or minerals found in the soils. The avoids cracking, expansion and contraction, of hardened concrete.
  • Sand free from organic impurities
The sand should be free from organic matter such as dead animals, decayed plant and other organic matters as they reduce the strength the mixed concrete also can undergo chemical reaction with other substances found in the soil.
  • Sand should be well graded
Well graded sand is the one contain continuous sizes of particles with appropriate proportion for each size this reduce the mount of water and cement required, increase the bond between particles which yield adequate strength of the concrete.

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