The Museum
* How it all began * The first calculation
program * Getting serious
SuperBeam 1 * More on
SuperBeam 1 * ProSteel 1
Making a computer produce calculations
Having purchased my own computer, one of my first serious projects was to try and write a program that could produce structural calculations. As a building surveying student at Reading University I was probably the only person in my set who had looked forward to the structural engineering classes and as a BCO was quite happy to check the simpler calculations.
Working out the bending moment and shear force from the loads was easy. I was somewhat stumped as to how to calculate deflections for non standard load cases until our tame checking engineer, Chris Weymouth, gave me a crash course in Mohr's theorem. He also explained that if one checked the beam at intervals of span/20 and took the maximum value one could be satisfied that this would be with a few percent of the actual maximum value. This was crucial in the days when there was a finite wait for the calculation to be done. If you're still around, Chris, I owe you a huge debt.
I cannot remember what the first version looked like, but as my Commodore PET only had a 40 character screen line length, it would have been less than sophisticated. A printout from that era does survive though:
The numbers at the ends of the dotted lines are times: that little block of steel lines took 18 seconds to print!
In 1982 I bought a BBC computer - at a recent meeting to commemorate its 25th anniversary it was said that the BBC had expected to sell 12,000 of them, but in the end sold well over a million. This explains why I, like many others, had to put my name on a waiting list and wait several months. The BBC computer was a class act with a much more sophisticated version of the BASIC programming language than the PET. My model B cost me £400; I later added a floppy disk drive which cost another £400, then moved on to a BBC Master.
In 1984 a colleague and I left Building Control to set a small design and build company. I was responsible for the design side and also started doing design work for a number of contractors, with an emphasis on loft conversions, which lots of people avoided because of the need for structural calculations.