STRESS
*When an external force is applied to a body, it tends to change the shape or size of the body. At the same time, an internal resisting force is setup within the body in the opposite direct to resist the deformation.
*The internal resistance per unit area of the body against its change in shape or size is known as STRESS.
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*Stresses are classified
1.simple stress (or) Direct stress
2.combined stress
3.Indirect stress
1.SIMPLE STRESS (or) DIRECT STRESS
*Stress induced within a body due to the single external force P applied perpendicular to the cross sectional area A is known as direct or simple stress.
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TYPES OF DIRECT STRESSES
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1.TENSILE STRESS
2.COMPRESSIVE STRESS
3.SHEAR STRESS
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1.TENSILE STRESS
When the external force acting perpendicular to the cross sectional area A of the solid body tends to elongate the body, the force applied is called tensile force and the stress induced in the solid body due to tensile force is called tensile force.
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2.COMPRESSIVE STRESS
The force compresses the body that the force is called compressive force and the stress induced in teh solid body due to compressive force is called compressive stress.
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3.SHEAR STRESS
When to equal and opposite parallel forces not in same line act on any two parts of a body, then one part tends to slide over or shear from the other part.such force which tends to make the adjacent plane in the body slide to relative to each other is called shear force. The stress induced in the cross section is called shear stress.
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2.COMBINED STRESS
When two or more external forces are acting on a body in different directions, the stress determined by combining the effect of these external forces is called combined stress.
Bending or twisting stresses in a structural member combined with direct tension or compression is called combined stress.
3.INDIRECT STRESS
If the stress is developed due to moment or torsion then it is called as indirect stress.
Ex: Bending stress
1.Bending stress
2.Torsional stress
1.Bending Stress
Bending stress is the normal stress that is induced at a point in a body subjected to loads that cause it to bend. When a load is applied perpendicular to the length of a beam (with two supports on each end), bending moments are induced in the beam.
2.Torsional Stress
Shear stress produced when we apply the twisting moment to the end of the shaft about its axis is known as torsional stress.
