Simulation of how buildings behave during an earthquake. The basic ideas comes from an old school book of mine called "Differential Equations with Boundary-Value Problems" by Zill and Cullen. The chapter itself is called "Earthquake shaking of multistory buildings." The basic idea is that you connect each floor with a spring and then simulate each spring with Euler Forward. The ground is moved with random values. You could find some real earthquake data to shake the ground, but you have to do that on your own!!!
This is how it looks in action:
Notice that this is an old video and the Unity project is a little simpler because I had to remove some stuff to fix errors after upgrading to latest Unity version!