Chapter 3 Architecture Architecture and Human Needs 1. Some buildings are designed to shelter life (house, apartment buildings) 2. House Governments (Capitol Building) 3. House commercial or business activities (skyscrapers) 4. Provide space devoted to worship gods 5. Designed to honor leaders (Lincoln memorial) Post and Lintel • Earliest and simplest methods of building with stone. • Involves placing a horizontal beam or lintel across the open space between two posts or other vertical supports. • Earliest examples from Egyptian temples dating back to 2700 B.C. • Tensile strength – the capacity of a material to withstand bending. Arch and Vault Construction • Early architects discovered they could span larger areas by placing a round arch made of stone on top of two supports. • Barrel Vault several arches placed front to back to enclose space. • Made it possible to construct buildings with stone roofs that could span a wide space. Arch and Vault Construction • Early architects discovered they could span larger areas by placing a round arch made of stone on top of two supports. • Barrel Vault several arches placed front to back to enclose space. • The barrel vault would weaken if holes were made for windows, so the interiors of these buildings were dark and gloomy. • Barrel Vaults of the Basilica Nova 312 AD. Roman Forum, Rome Groin Vault • Roman builders began using a groin vault, two barrel vaults placed at right angles. • This architecture allowed for four openings to the interior space. Groin Vault Flying Buttresses • Middle Ages church builders sought other solutions to the problem letting light into the interior. • Plus the height of churches meant power and closer to God • A pointed arch was introduced to achieve both height and light. • Flying Buttresses were required to create a thrust-counterthrust to support the walls and weight of the roof • The use of flying buttresses allowed the builders to fill the spaces between the supporting piers with spectacular stained-glass windows Dome Construction • A Dome is a hemisphere placed on walls that enclose a circular or square space. • Developed first in the Middle East then later in ancient Rome. • Pantheon - Rome Modern Construction Processes • Wood Framing – originally based on the post and lintel system. • Changed dramatically beginning in the 1800’s when metal nails were manufactured in quantities and sawmills provided lumber in standard sizes. • Balloon Framing – heavy posts and beams built a self supporting system • Strength is added as the building comes together. Iron and Steel Construction • 19th century brought the development of iron technology. • Metal was used more frequently to build the framework of large buildings and monuments, such as the Eiffel Tower. • Steels great strength allowed vast interiors and lots of glass. • Steel has great tensile strength. • Steel skeletons are self-supporting skeletons. • By 20th century steel was used throughout the world, leading to skyscrapers. Reinforced Concrete Construction • Concrete, an important building material in ancient Rome, was not used again until the end of the 18th century. • Used to build lighthouses. • 19th century builders realized they could reinforce it with metal rods before it hardened. • Known as ferroconcrete, or reinforced concrete. Lightweight Structural Systems • Lightweight metals and plastics offer contemporary architects new and exciting materials. • Internal frames made of intricate metal rods with spaces between filled with metal, glass, plastic or some other material. Review facts • In what way is the barrel arch an improvement over the post and lintel? • Why is it possible to only span narrow space with stone? • How is the barrel vault constructed? Why were buildings constructed with barrel vaults dark and gloomy? • What brought about the dramatic change in the wood construction in the 19th century? • What was the purpose of a Flying Buttress?