COE 3001 Lecture 8: 8+Torsion

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

Document Summary

So far we have only considered the simplest loading scheme axial loading of a straight bar. This was a useful starting point because axial loading is a straightforward but effective system for studying normal stresses. Now we will consider a loading configuration known as torsion. Torsion is the twisting of a straight bar when loaded by moments that produce rotation around the longitudinal (long) axis of the bar. To understand torsion, we begin at a familiar starting point: a prismatic bar, in this case with a circular cross-section, twisted by torques t at the ends of the bar. We will typically illustrate these torques with curved arrows (in the direction of twist) or as double-headed arrows (in the direction of the moment, by the right hand rule). Since the bar is prismatic (i. e. , every cross-section is identical) and every cross-section is subjected to the same internal torque t, we say that the bar is subject to pure torsion.