- 1 What is Concrete
- 2 Classification of Concrete
- 2.1 1) According to specification
- 2.2 2) According to the level of control
- 2.3 3)According to binding materials
- 2.4 4) According to design
- 2.5 5) According to purpose
What is Concrete
When a binding material (cement or lime), fine aggregate (sand or surkhi), coarse aggregate such as crushed stone, broken bricks, etc. and water are mixed in suitable proportion, they form an easily workable mix, known as plastic or green concrete. When this plastic concrete becomes hard like a stone, this is termed as hardened concrete or simply as concrete.
Classification of Concrete
The concrete are classified as given below :
1) According to specification
a) Nominal mix concrete
The concrete which is prepared according to prescriptive specification i.e. proportion of constituents and their characteristics is termed as nominal mix concrete.
b) Designed mix concrete
The concrete which is prepared according to performance-oriented specifications i.e. strength, workability, etc. is termed as designed mix concrete.
2) According to the level of control
a) Controlled concrete
Controlled concrete is that concrete, in which the preliminary test is conducted for designing the mix. In addition, to mix proportioning, level of control is also exercised in the selection of materials batching, mixing, transportation, compaction and curing along with necessary checks and tests for quality acceptance.
b) Ordinary concrete
Ordinary concrete is one where no preliminary tests are performed for designing the mix.
3)According to binding materials
a) Cement concrete
The concrete consisting of cement, sand and coarse aggregate mixed in suitable proportion in addition to water is called cement concrete.
b) Lime concrete
The concrete consisting of lime, fine aggregate and coarse aggregate mixed in suitable proportion in addition to water is called lime concrete. The strength of this concrete is less but it is cheaper than cement concrete.
4) According to design
a) Plan cement concrete.
b) Reinforced cement concrete.
5) According to purpose
a) Vacuum concrete.
b) Air entrained concrete.
c) Lightweight concrete.
d) Sawdust concrete.
e) High early strength concrete.
f) White and coloured concrete.