DegreeTutors/Multi-Degree of Freedom Dynamics, Modal Analysis and Seismic Response

  • $79

Multi-Degree of Freedom Dynamics, Modal Analysis and Seismic Response

Build the knowledge and tools to decode the dynamic response of real-world structures to real-world loads

Contents

1. Welcome and preliminaries

In this short introduction section, I’ll set out a roadmap for the course and give you a sense of what to expect. This will give you a good idea of what we’re going to cover during this course. I’ll also briefly comment on assumed prerequisite knowledge - in other words, what you should have covered before taking this course, and also what you don’t necessarily need to know.
1. Introduction and course overview
Preview
2. Course prerequisites and do I need to know Python?
Preview
Support and Lecture Q&A (Please read!)
3. Getting your coding environment set up
Preview

2. Introduction to ground motion modelling

This section starts by covering some of the fundamental topics in the context of SDoF systems. We’ll look at developing analytical solutions to harmonic ground motion before expanding to numerical solutions for realistic ground motion. The section is focused on covering a number of core topics and plugging some gaps in our understanding of SDoF dynamics before moving on to multi-degree of freedom systems in the next section.
4. Section overview
Preview
5. Overview of earthquake ground motion
6. Capturing the influence of ground motion
6.1 Jupyter Notebook - (lecture 6)
7. Motion transmissibility and isolation
7.1 Jupyter Notebook - (lecture 7)
8. Simulating ground motion response
8.1 Jupyter Notebook - (lecture 8)
9. Realistic ground motion response
10. Integrating ground acceleration
10.1 Jupyter Notebook - (lectures 9-10)
11. Introduction to response spectra

3. Modelling Multi-DoF Dynamic Systems

In section 3 we introduce the multi-degree of freedom (MDoF) system and the shear building dynamic model. We discuss the coupled nature of MDoF systems that makes them a challenge to model. We’ll explore numerical solutions strategies by building our own DIY central difference algorithm and then implementing some off-the-shelf solution toolboxes.
12. Section overview
Preview
13. Introduction to MDoF systems
14. MDoF Equations of Motion
15. Direct integration of the coupled EoM
16. Solving the coupled EoM by direct integration
17. Using SciPy’s ODEINT solver
17.1 Jupyter Notebook - (lectures 16-17)
Mid-course check-in

4. Modal Analysis and Decoupling the Equations of Motion

In section 4 we cover the most important topic in the course - modal analysis. We’ll spend plenty of time here making sure you understand concepts like mode shapes, orthogonality and what it means to uncouple the equations of motion. You’ll see that modal superposition as a solution strategy offers us major advantages over the direct integration we discussed in the previous section. By the end of this section, you’ll have a deep understanding of modal analysis and be comfortable implementing it.
18. Section overview
Preview
19. What is modal analysis and how does it help us?
20. Finding natural frequencies and mode shapes
20.1 Jupyter Notebook - (lecture 20)
21. Matrix representation and the eigenproblem
21.1 Jupyter Notebook - (lecture 21)
22. Modal matrix and mass normalisation
22.1 Jupyter Notebook - (lecture 22)
23. Orthogonality and Decoupling Equations of Motion
24. Modal superposition - forced vibration
25. Comparing modal superposition with direct integration - forced response
26. Visualising the forced vibration response
26.1 Jupyter Notebook - (lecture 24-26)
27. Modal superposition - free vibration
28. Compare modal superposition with direct integration - free vibration
28.1 Jupyter Notebook - (lecture 27-28)

5. Damping Orthogonality

In section 5 we deal with damping. We’ll see that the same uncoupling of the equations of motion we discussed in the previous section cannot be directly applied to the damping matrix. In this section, we’ll explore how to derive a damping matrix that provides predictable levels of damping in each vibration mode. This section is important as it equips you with two complete and equivalent solution strategies; direct integration and modal superposition. We’ll finish out this section by demonstrating the equivalence of both. 
29. Section overview
Preview
30. Rayleigh damping
31. General determination of the damping matrix
32. Calculating the damping matrix
32.1 Jupyter Notebook - (lecture 32)
33. Direct integration versus modal superposition for a damped system
33.1 Jupyter Notebook - (lecture 33)

6. Bringing it all together: N-storey response to earthquake ground motion

In the final section, we’ll take everything you’ve learned up to this point and build out the final capstone analysis code. At this point you’ll understand the theory and how it can be mapped into code - now we can emphasise coding efficiency and build a solution script that easily scales to larger numbers of degrees of freedom with no extra effort on our part. By the time you complete this course, you’ll have a toolbox full of dynamic analysis tools and the knowledge and confidence to apply them to your own projects. 
34. Section overview
Preview
35. Equations of motion N-storey shear building
36. Automating modal analysis for NDoF
37. Ground motion response using modal superposition
38. Base shear and overturning moments
39. Visualising the structural response for NDoF
39.1 Jupyter Notebook - (lecture 35-39)
40. Course wrap up and completion certificate