Full Stone Arch

This stone arch is around the corner from my home. This is an entrance to an office setting. Each one of the stones are loose. No mortar was used or any re bar. If you notice two metal rods with the flat bars on the end. This is what is holding the arch together. Notice how the top stones are tapered, wedge shaped. The wedge shape is what keeps the stone from falling through. The top of the arch stone is wider than the bottom of the arch stone. Have you ever noticed man hole covers in the street? Every man hole cover is round. This is for a reason. The cover can not fit through the hole, so it can not fall through and hit a worker in the hole. The forces on the arch are straight down and outwards to the sides. The bar keeps the columns from falling outwards. If the arch and columns were in a wall section, the metal rods would not be needed to hold the arch together. This is a great entrance for the office, and it is very neat to pass by and look at daily.