Lecture
This lecture covers the derivation and application of the principle of virtual power in the context of Finite Element Method (FEM). Starting from the principle of virtual power, the instructor explains how to find approximate true solutions for displacement and stress in specific material problems. The lecture delves into the interpretation of virtual power as the time derivative of virtual work, leading to the understanding of virtual velocity and displacement. The concept of strain is introduced, followed by the application of the principle of virtual work to find solutions for boundary value problems. The lecture concludes with the development of the symmetric velocity gradient and its significance in the context of FEM.