1.4 STRAIN

1.4   NORMAL STRAIN (e)

When a force P applied to a material, deformation will occur on the material. The ratio of the material deformation strain is called Normal. Normal strain is defined as an extension or shottening had happened to the size of the material per unit length.

There are no units for strain because it is a ratio, while the shortening of the unit for extension @ original length is m. Strain can also be broken down into two types: Axial Strain and Strain side. Axial strain is also referred to as longitudinal strain, occurs in the direction of the applied force, while the lateral strain occurs in the direction perpendicular to it. For rods, the definition of axial and lateral strain can be simplified as follows.

 For elastic materials, these strains have a relationship, where a constant can be formed, called the Poisson ratio, (V). Poisson's ratio can be defined as the ratio of lateral strain to axial strain.