 
We noticed this arch near one of the entrances to a section of the park, and we were reminded of the bridge-building segment in Science 8. Not only are arches attractive, but they are very strong. Arches were traditionally constructed from stones. The weight of each stone, a downward force, is vectored along the stones that form the arch; each stone presses on the one next to it. As long as the base is firmly anchored, the stone arch doesn't even require mortar.
In fact, many of the ruins of cities, bridges, and aqueducts (water-carrying pipelines supported above the ground) that were built by the Romans several thousand years ago are still standing, and still as strong as the day they were built, largely because of the strength of their stone arches. Arches were used frequently in building construction since that time; they can be seen in doorways, bridges, and windows in structures all over Europe. Visit our model bridge-building pages for more information about bridge structures. |