I have been working on this general solution for the second order ODE suggested by Fryba in 1968.
he had coded it on a URAL 2 computer, - it is a good read on Wikipedia
I am close to sorting out his equations and getting the old algorithm to run. Unfortunately the original author has a few minor issues with the 1968 English version of the paper, some of the symbols are not defined, but that is only a small challenge.
I was looking at the results this morning and the ODE solution is expressed as a finite Fourier (sine) integral transformation
I plotted the results of the first four elements of the Fourier series and have included them in a ppt file. -- I thought it was interesting to look at a real Fourier series broken down
The secondary wave is caused by Fryba having a flat spot on the wheels and this affects the load function -- I need to sort out his equation as it has dimensional issues.