Beam-Column Elastic Foundation — Lesson 5

This lesson covers the stability analysis of a continuous beam-column and the calculation of the critical load. It delves into the problem of buckling of a bar on an elastic foundation, explaining how the action of equally spaced elastic supports of equal rigidity can be replaced by the action of a continuous elastic medium. The lesson further discusses the calculation of strain energy for the deflection of an elastic foundation and the bending of the bar. It also explains how to calculate the work done by the compressive force and how to find the critical load. The lesson concludes with the calculation of the critical load of a hinged bar.

Video Highlights

00:46 - Explanation of the beam on elastic foundation problem
08:09 - Calculation of the strain energy for the bending of the bar
13:54 - Calculation of the work done by the compressive force
22:33 - Discussion on the change in the number of half sin waves with the change in the modulus of foundation
30:34 - Conclusion of the critical load being twice the buckling load of a hinged bar

Key Takeaways

- The stability analysis of a continuous beam-column involves calculating the critical load.
- The buckling of a bar on an elastic foundation can be represented by the action of a continuous elastic medium.
- The strain energy for the deflection of an elastic foundation and the bending of the bar can be calculated using specific formulas.
- The work done by the compressive force can be calculated by integrating the square of the deflection.
- The critical load can be found by equating the strain energy stored to the external work done.
- The critical load of a hinged bar can be calculated by considering the number of half sin waves and the modulus of the foundation.