Strength of materials
Strength of materials deals with the effect of forces on deformable bodies. In addition, material-dependent parameters should be considered as well. An introduction to the strength of materials is, therefore, given by the concept of stress and strain and by Hooke’s law, which is applied to tension, pressure, torsion and bending problems.
The load from external forces causes stresses in the components. The mesh of the material is deformed under the action of a force, e.g. compressed, stretched etc. Elastic deformation means the atoms return to their original position after the action of the force has ceased.
Long and slender components such as rods, beams, supports etc. may end up in indifferent or unstable equilibrium states and buckle if they are exposed to a force along the rod axis under compressive stress. The mathematician and physicist Leonhard Euler defined four typical buckling cases to calculate the buckling force in rods.
Experimental equipment to investigate components in which two or more basic stresses are present simultaneously.
Two methods of non-destructive experimental stress and strain analysis are presented here:
- the electrical method of strain measurement using strain gauges to indirectly determine the actual stresses
- the photoelastic method for a direct representation of the stress distribution.