Arches

Arches were originally uses for utilitarian and underground structures. An example of this would be storehouses or drains. They reached their main popularity in Gothic architecture but seemed to be uncommon in more modern architecture. The main purpose of the arch is that it allows the spanning of masonry walls, or walls made of items mainly held together with the use of mortar.  As stated from the book arches are “a pure compression structure and therefore ideally suited to materials such as stone or brick that are strong I'm compression but weak in tension. Also arches have outward thrust at their bases and the book says that this must be resisted to ensure stability.

Romans were the first to really take advantage of the use of arches. As we have seen they used them in many structures like aqueducts and imposing bridges. They were also used in the widely known coliseum. Because of the Romans liberal use of arches they became the first metropolis with a population of more than a million.

Coliseum:

 

Arches are also used to create structures like vaults which are basically a large continued hallway of an arch. They when they are rotated they enabled the creation of structures like domes.

The strongest forms for arches are given by a parabolic shape and have catenary curves.  These formed the basis of the Cantalan system of vaulting and were exploited by Antoni Gaudi

Parabolic Arch:

In the book it said that arches are not normally seen in modern architecture. This is because now-a-days we have materials like steel and reinforced concrete that is strong in both compression and tension. 

Reinforced concrete example:                                           

Lots of Steel tubes: 

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