Sunday, 21 July 2019

# 3 Types of Strain every Engineer must know-Normal Strain,Shear Strain & Volumetric Strain

3 Types of Strain every Engineer must know-Normal Strain, Shear Strain & Volumetric Strain: When you are going for any Interview, every recruiter will ask some questions and out of those questions, this question was also in the list. As we know about only one strain i.e.change in dimension to its original dimension but, when the recruiter asks about the types of strain, we will be looking here and there. Therefore, In this Article, I will be explaining about 3 Types of strain along with their representation. ## 3 Types of Strain every Engineer must know:

The 3 types of strain are as follows.

The detailed explanation of all these Types of Strain is presented below.

1.Normal Strain:

• It is defined as the ratio of change in dimension to its original dimension.
• It is due to the normal forces and it is represented by e or ε.
• It is a dimensionless parameter.

If we consider the dimension as Length then Change in length to its original length is the Normal strain and it is represented below.

Let “L” be the Length of the component and “dL” will be the Change in Length of the component then the representation of the Normal strain is

 e or ε = dL/L

2.Shear Strain:

• It is defined as the angular distortion between any two mutually perpendicular planes in radian’s is the shear strain.
• It is due to shear force or tangential force acting on a specimen.
• It is represented by gama(γ).

Representation:

Consider a component which is subjected to equal and opposite forces on either face (AB&CD) and one end of the face(AB) is fixed and the other end(DC) is kept free. Due to the application of force on one of the face, the component gets distorted through an angle of φ to the shape ABC’D’.

Now Shear strain or deformation per unit length is of the component is = CC’ / CD = CC’ / BC = * radian

3.Volumetric strain:

• It is defined as the ratio of change in volume to its original volume.
• It is due to the normal forces only.
• It is a dimensionless parameter.

Representation

This means that the volumetric strain of a deformed body is the sum of the linear strains in three mutually perpendicular directions.

• Due to normal forces, there will be dimensional and volumetric changes.
• Due to shear, there will be distortion in shape without a change in volume.
• Stress depends on strain.strain is an independent parameter and stress depends on strain.

This is the complete explanation of all the 3 types of strain in a detailed manner. If you have any doubts, then you can ask us from the comments section.