Single DOF Stability Model and Model Having Imperfection — Lesson 2

This lesson covers the concept of stability models and how to determine the critical load using three common approaches: equilibrium, kinetic (dynamic), and energy. It delves into the characteristics of equilibrium positions and conditions of equilibrium using the energy method. The lesson further explores two single degree of freedom rigid body models and a stability model with imperfect geometries. It demonstrates how to predict the critical load for perfect geometry from an imperfect one. The lesson also explains how to calculate the total potential energy of a system in a deformed configuration and how to find the equilibrium position and characteristics of equilibrium.

Video Highlights

00:39 - Discussion on the characteristics of equilibrium positions and the use of the energy method
05:48 - Discussion on the equilibrium condition and the first variation of the total potential energy
13:50 - Introduction to another stability model and the objective to find the critical load
21:15 - Explanation of the stable and unstable equilibrium conditions for the new model
28:41 - Discussion on the hyperbola representation in the coordinate system

Key Takeaways

- The three common approaches to find the critical load in a stability model are equilibrium, kinetic (dynamic), and energy.
- The energy approach helps in understanding the characteristics of equilibrium positions.
- The total potential energy of a system in a deformed configuration can be calculated using the energy approach.
- The equilibrium position can be found by making the first variation of the total potential energy equal to zero.
- The characteristics of equilibrium can be determined by finding the second variation of the total potential energy.
- It is possible to predict the critical load for perfect geometry from an imperfect one.