As the title states, how do wooden bridges hold the weight of trains?
I’m specifically speaking of steam locomotives in the late 1800s.
I know there is some sort of engineering involved, and I know there’s a lot of wooden beams and some sort of science behind the angles and supports but I just don’t get it and I would like to understand.
Thank you!
In: Engineering
Wood is surprisingly strong. It can keep huge trees with big wind-catching leaf canopies upright even in a hurricane. Immagine how heavy an entire tree is too. The base of the tree has to support that weight and the some to not crush under the weight.
The strength of 3 or 4 trees could probably support the weight of a train too. So engineers (the calculator kind, not the choochoo kind) make sure that through all the positions of the train on the bridge, there are always atleast 3 or 4 (or however many they think are necessary) trees taking the weight of the train all the way to the ground.
And actually, its not just trains that are trying to flatten a train bridge! That same hurricane could blow it over sideways, and might be stronger than the train can push down! And earthquakes make forces that get bigger the more material you use, and the stiffer the structure is. So there are lots of ways the wood needs to be positioned to keep it up.
Latest Answers