COE 3001 Lecture Notes - Lecture 7: Energy Density

• School: Georgia Tech
• Department: College of Engineering
• Course: COE 3001
• Professor: Thomas Susan

Document Summary

The work done to elongate the bar is equal to the area under the force-elongation curve and is described by: When we load the bar, we generate strains in the bar. These strains increase the energy of the bar, so we can define a quantity called strain energy, u, which is equal to the energy absorbed by the bar during loading: Using the relationships we have for axial loading of a linear elastic material, we can express the strain energy stored in an axially loaded, linear elastic bar either in terms of the elongation or the applied force: We can extend these relationships to nonuniform bars: First, because strain energy is not a linear function of force, we cannot determine strain energy by superposition principles. Second, whether a bar is subjected to tension or compression, work is done (and energy is stored) in the bar regardless.