Concrete is one of the inevitable material in construction, even though new products has introduced in the field but those materials will not replace the Concrete.
In this article, we are going to discuss the properties of concrete.
What is Concrete?
Concrete is a blended material of cement, sand and coarse aggregate or lightweight material. The concrete will become a harden element when the chemical reaction happening between cement and water.
Cement is a binding material, its bind the aggregates and formed as a hardening element.
We just take a look about the advantages and disadvantages of concrete before to know the properties of concrete.
Advantages and Disadvantages of concrete
Advantages of concrete
- Concrete has a high compressive strength and corrosive and weathering effects are minimal.
- Economical and little maintenance if required.
- Concrete can be sprayed and filled into the cracks.
Disadvantages of concrete
- Concrete is strong in compression and weak in tension so the steel reinforcement required.
- Contraction joints or Expansion joints have to be provided in the concrete to avoid the cracks development due to the shrinkage or moisture.
- Concrete is liable to disintegrate by alkali and sulphate attack.
Properties of Concrete
- Green Concrete (Fresh Concrete)
- Harden Concrete
What is Workability of Concrete
The concrete can easily be transport, placed and compacted without segregation and bleeding is called workability of concrete.
The Workability of concrete depends on the quality of material, appropriate mixing and water-cement ratio.
We can measure the workability of concrete by the Slump Test.
Bleeding of Concrete
The appearance of water with cement in the freshly laid concrete surface when compacting the concrete. The concrete bleeding happening due to the excess compaction or excess water in the concrete mix.
It creates the pores in the concrete and weak. The quality of material, water-cement ratio and proper compaction will avoid the bleeding.
Segregation of Concrete
The separation of aggregates from the fresh concrete which results in non-uniformity is called segregation.
Due to the aggregates, segregation honeycomb may form in concrete and it decreases the strength of the concrete.
Harshness of Concrete
The concrete becomes the hardened surface after its complete setting time. The hard surface resists the load against the compression.
- Creep of Concrete
- Thermal Expansion
- Changes in Dimension
Strength of Concrete
The strength of concrete is its resistance to bear the compression load after it has hardened. Basically, the strength of concrete has taken from the 28 days test results for the structural design. Because the concrete gains the strength beyond 28 days.
The grade of concrete listed based on the characteristic strength of concrete. The concrete strength has measured by the compressive & tensile test.
The compressive strength of concrete depends on the following factor
As discussed above the same factor applicable in the Tensile test.
But as discussed in above the concrete have low resistance against the tensile load. Generally, the tensile strength of concrete will be in the range of 10 to 12 percentage of its compressive strength.
Durability of Concrete
The Durability of concrete is the resistance against the environment like weathering, chemical attack and corrosion.
Normally the concrete having better durability. Sometimes the steel may corrode if the concrete having porous.
Shrinkage of Concrete
The shrinkage of concrete depends upon the components of the concrete like the size of the member and weathering conditions.
The approx value of the shrinkage strain is 0.0003 as per the IS code 1343.
Creep of Concrete
The inelastic deformation of concrete while applying the compression load is called creep of concrete.
The Stress in concrete should not exceed 1/3rd of its compressive strength.
|Age at Loading||Creep Co-efficient|
Change in Dimension
The dimensional changes in concrete may happen due to the shrinkage, plasticity and creep of concrete. The dimensional changes may lead to the formation of the crack.