What is concrete? – Ingredient of concrete?

Concrete is the most widely used man-made construction material in the work and is second only to water as the most utilized substance, on the planet. It is obtained by mixing cementing materials water, aggregate, and sometimes admixtures in the required proportion. The mixture when placed in forms & is allowed come to harden into a rock-like mass known as concrete. The hardening is caused by chemical reactions between water and cement & it continues for a long time & consequently, the concrete grows stronger with age.

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Strength, durability & other characteristics of concrete depend on the properties of its ingredients the proportion of mix the method of composition, and after-control during placing. Compaction & curing. The popularity of concrete is due to the fact that from the common ingredients. It is possible to tailor the properties of concrete to meet the depends of any particular situation.

The key to producing strong, durable & uniform concrete that is high performance by strong, durable & uniform concrete i.e, high-performance concrete lies in being careful of its basic & processed components. These are the following ingredients:-

It is the most widely used cementing ingredient in present-day concrete that consists of compounds Ca, Si, Al, Fe & O2. It is an extremely ground material having adhesive properties which provide a binding medium for the discrete ingredients, identification of the major complex compounds is largely based on bojuis work & these are called bojuis compounds.

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S.N.	NAME	CHEMICAL FORMULA	PERCENTAGE
1.	Tri calcium silicate(C3S)	3CaO.SiO2	30 – 50
2.	Dicalcium silicate (C2S)	2CaO.SiO2	20 – 45
3.	Tri calcium aluminate (C3A)	3CaO.Al2O3	8 – 12
4.	Tetra calcium aluminate ferrite (C4A)	4CaO.Al2O3.Fe2O3	6 – 10

S.N.	CONSTITUTES	PERCENTAGE	AVERAGE
1	Lime (CaO)	62 – 67 %	63
2	Silica (SiO2)	17 – 25 %	20
3	Aluminum (Al2O3)	3 – 8 %	6
4	Iron oxide (Fe2O3)	0.5 – 6 %	3
5	Magnesium oxide (MgO)	0.1 – 4 %	2
6	Sulfate trioxide (So3)	1 – 3 %	1.5
7	Soda & potash (Na2O + K2O)	0.5 – 1.3 %	1

these are mainly naturally granular materials such as sand, gravel, and crushed stone. However, technology is the use of recycled material & synthetic products.

These are the ingredients in concretes other than Portland cement, water, and aggregate that are added to the mixture immediately before or during mixing to reduce the water required to accelerate or improve specific durability characteristics.

It is also called mineral additive, it contributes to the properties of hardening concrete through hydraulic or pozzolanic activity. Typical engineering of natural pozzolanic is fly ash and silica fumes.

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