Sand is essentially quartz and it is called fine aggregate when it is between 4.75mm and 0.15mm in size. Sand is procured in trips of trucks and should be delivered without impurity.
Impurity in concrete affects the quality and strength of concrete. Suitable sand for concrete construction can be sourced from pits, river beds and banks, stream etc. Dredging of river beds is a major source of sand for concrete. Silt and clay sands are not suitable for construction purposes due to the high content of sulphur. Sulphur attacks concrete and affects the quality and strength of the concrete.
“Local sand can be used to make concrete as importation adds to the cost. Availability of suitable sand for concrete is becoming scarce and expensive hence; alternatives are being developed such as crushed rock and fly ash” (Varghese, 2006).
No comments:
Post a Comment