Characteristics of Cement & Sand as building materials
The cement stands for a ground material that is formed with the compound of lime, silica, alumina and iron. It retains the concrete & mortars jointly. Generally, three types of cements are available :-
Given below, the details about different types of cements which are commonly used:-
Portland Pozzolana Cement
It adheres to IS 1489. It is formed by combining fly ash (from thermal power plant) with clinker & gypsum. Portland cement clinker is grinded with pozzolana to build up this type of cement.
Portland Slag Cement
It adheres to IS 455. It is formed by combining superior quality blast furnace slag (from iron steel industry) with clinker.
Ordinary Portland Cement
- 33 grade adhered to IS 269
- 43 grade adhered to IS 8112
- 53 grade adhered to IS 12269
The grade number denotes the least compressive strength of mortar made of cement & sand in N/mm2 at 28 days.
It is formed by amalgamating clinker & superior quality gypsum. Initially, the mixture of calcareous (calcium carbonate) & argillaceous (clay) are burnt at a very high temperature to develop ordinary portland cement. Then, the product (clinker) is grinded with little amount of gypsum to produce a fine powder called as ordinary Portland cement.
The ordinary portland cement with grade 43 are utilized in all the works undertaken for the skyline site.
Sand is another useful building material. Generally, the following types of sands are used in construction work.
This type of sand comprises of 90% of particles containing size in excess of 0.6 mm and less than 2 mm.
This type of sand comprises of 90% of particles containing size in excess of 0.2 mm and under 0.6 mm.
This type of sand includes 90% of particles containing size greater than 0.06 mm and lower than 0.2 mm. While selecting perfect type of sand, it should be clear, angular & hard, does not contain clay, mica & soft, flaky material graded. It should be a blend of fine, medium and coarse sand without any contaminates. Contaminates like sea salt persist in moisture (water) content should not go beyond 7%. While mixing the concrete, the moisture content should be taken into consideration.
The price of sand comprises of three or four component-base cost like transportation, handling & intermediaries. The cost of sand is reduced if it is obtained directly from the source in bulk quantity.