Introduction to Strength of Materials

Introduction:-

In earlier research we've got passed through a primary direction in mechanics of Rigid Bodies, more typically referred to as Engineering Mechanics or Applied Mechanics. Mechanics as such is subdivided into 3 branches; Mechanics of Rigid bodies, Mechanics of Deformable Bodies and Mechanics of fluids.

Mechanics of Rigid Bodies assumed our bodies to be flawlessly inflexible i.E. There's no deformation of our bodies underneath the motion of masses to which they're subjected statics and Dynamics are the 2 branches of Mechanics Of inflexible Bodies related to stationary and transferring bodies respectively below the movement of masses.

Stress:-

i. The force of resistances in step with unit are provided through a body against deformation is known as Stress. When a body is subjected to outside loading the body undergoes a few deformation. At the equal time internal force of resistance is because of the concord of molecules within the frame. Thus strain is precipitated inside the body upon outside action of load

ii. If the frame is able to resist the external load, it's miles said to be solid, in equilibrium and consequently for this condition the internal force of resistance must be equal to the external load.

By Definition Stress=force of resistance/pass sectional place

Or Stress=P/A

Strain:-

As the body produce pressure of resistance to counter the external loading it undergoes some deformation. The quantity of deformation depend on the cloth belongings like molecular concord. The ratio of exchange in size is known as pressure.

Since Strain is ratio, it has no gadgets. We shall denote pressure by using letter e. If L is the unique size and is change in measurement and then

Strain =Change in measurement/Original dimension

Types of Stress:-

1) Direct Stress and Direct Strain:-

When the pressure of resistance acts normal or perpendicular to the region on which it acts, the strain so produced is named as Direct or Normal Stress and corresponding strain is known as Direct Strain.

We shall denote direct pressure through letter 'f'. Direct strain might be of tensile nature of compressive nature.

2) Tensile stress:-

When the pressure of resistance acts faraway from the go sectional region, the direct stress is of tensile nature. Tensile stresses have a tendency to cause an increase in the unique dimension.

3) Compressive Stress:-

When the pressure of resistance acts toward the go sectional location, the direct pressure is of compressive in nature. Compressive stresses generally tend to reason a lower inside the unique dimension.