Principal Stresses and Strains:

In the principal stresses and strains, you have already been introduced to easy states of stress. Stress Analysis is a necessary requirement in the evaluation of strength, stiffness, deformations and safety of solids so in which one might generates functionally efficient and economic designs. There is a huge number of ways in that stresses are induced in solids (a few samples ones you have already learnt), that will engage your attention in the subsequent units. Here, we shall be concerned with the analysis of a given state of stress (expressed in terms of stress components on selected planes) which will have a bearing on the analysis of strength and safety of solid components.

Objectives

After studying the principal stresses and strains, you should be able to

1 describe six stress components on mutually perpendicular planes at the requisite location,

2 define the principal plane and principal stress,

3 recognize the plane of maximum shear stress,

4 analyse the state of stress within combined bending and shear and combined bending and torsion, and

5 define several theories of failure.