1. Arch Structures
ID2-125: English for Architecture and Urban Planning II Daniela García

2. Table of contents Introduction Definition of an arch
Etymology and History
Parts of an arch
Types
Technical aspects
Uses and common materials in arches
Famous arches
Conclusions

4. Arches: what are they?
An “arch” is a curved structure that spans a certain distance and supports the structure and weight above it. Traditionally, an arch is composed of pieces called voussoirs that always work in compression and can take various curved shapes.

5. Etymology
History
Arch comes from Old French arche ‎(“an arch”), a feminine form of arc, from Latin arcus ‎(“a bow, arc, arch”), derived from Indo-European arkw (“bow”).
Arches appeared as early as the 2nd millennium BC in Mesopotamian brick architecture. Many civilizations used arches infrequently around this era, using arches as structures for underground passages.
Their systematic use started with the Ancient Romans who were the first to apply the technique to a wide range of structures, creating aqueducts.
The Romans learned the arch building techniques from the Greeks, but were they the first to fully understand arches and take advantage of its qualities.

6. Schematic illustration of an arch
Keystone.
Voussoir.
Back.
Impost.
Intrados.
Rise.
Clear span, “Bay”.
Abutment.

7. Types

8. Types

9. Forces acting on the structure
Technical aspects
Eliminates tensile stresses.
All forces are compressive, making stone, cast iron and concrete a perfect material for it due to their resistance to compressive stresses rather than tensile.
Supports heavy weights because of its shape, distributing forces through all the arch.
It doesn’t require framed structures to be built.
The weight pushes the arch’s base, and this needs to be restrained with friction or heavier bases.
Forces acting on the structure

10. Uses Bridges Gates Windows Passages/Arcades Commemoration Vaults Domes
Aqueducts
Decoration

11. Common Materials
Stone
Concrete
Metal
Brick
Wood

12. Famous arches Flavian Amphitheatre (Colosseum), Rome, Italy.
Triumphal Arch of the Star, Paris, France.
Alcalá Gate, Madrid, Spain.
Gateway Arch, Missouri, USA.
Rua Augusta Arch, Lisbon, Portugal.
Federation Arch, Caracas, Venezuela.

13. Conclusion
Due to their versatility, arches were and still are being used in contemporary buildings.
This structure represents an advance in the architectural fields and history because of its ease to be constructed without anything but raw materials as stones.
The shape or materials of an arch can vary depending on its purpose (weather, weight supported, size durability, resistance to fire).
It can replace beams and columns in large constructions.

14. Arch Structures, by Daniela García
Thank you for your time!
Arch Structures, by Daniela García