Ezra Shaw, Getty ImagesTo put it in context, when the bridge was designed and built:
- There were no calculators - as we know them now, "calculators" in the 1930s were office clerks who would spend months solving a single linear system of equations, as is required for an indeterminate structure such as this. This can be accomplished in seconds now even on the cheapest laptop. The command in Matlab is "x = Ab". We have it easy.
- There were no total stations - setting the bridge out was done with theodolites and good eyesight! Coordinates, angles, and distances were all calculated manually. There were no laser sights or satellites to check the GPS coordinates of the reference points.
- There was no Microsoft Project - planning and delivery of such a complex project was again carried out manually with (obviously) no help from a computer. Network path analysis was in its infancy, and yet the bridge was built in a nifty 51 months.
- There was no limit state design or partial factor format codes of practice - instead allowable stress design was used, with far less information available on the material performance under cyclic and dynamic loading than we have today. Aerodynamic forces were not understood nor worried about - the Tacoma Narrows Bridge collapse was a decade later.
- Finally, and just to get my research in, there was of course no traffic microsimulation assessment of the loading that the traffic would impart to the bridge. This would come nearly 75 years later!