Lecture
This lecture covers the application of the displacement stiffness method to torsional statically indeterminate problems, both internal and external, including stress concentration, torsion of non-circular members, and inelastic members. The instructor demonstrates how to analyze composite bars under torque, calculate reaction torques, maximum shear stresses, and angles of twist. The displacement stiffness method in matrix form is explained for treating statically indeterminate systems in torsion, with examples provided for both internal and external indeterminacy cases.