Innovations in the 20th Century

The construction during the late 19th up to the mid-20th Century can be identified by one predominant structural form -- the High Rise. This type of structure was usually constructed with either concrete or steel.

• The High Rise Using Steel Frame Construction, and
• The High Rise Using Concrete Construction

The High Rise Using Steel Frame Construction: The first tall structure using steel as its principal building material was the Eiffel Tower in Paris. It was 300 m (1,000 ft) tall. Its height was not challenged until 1929. But the major innovation was the development of the steel frame, as a structural element. The home of the high rise is Chicago, where the first metal structure was built -- the 10-story Home Insurance Company Building in 1885. The metal framing used in this building was completely encased in brick so as to render it fireproof. The Manhattan Building was the first to use vertical truss bracing to resist wind forces. The first all-steel building was the Ludington Building in 1891. (For details and images of these skyscrapers, please check out the link below for Skyscrapers in Chicago.)

Soon standard construction practice for high rise structures included the steel frame of rolled steel I-beams, riveted and/or bolted connections, diagonal wind bracing, brick or clay tile fireproofing and the caisson foundation. Vertical transportation was by electric-powered hydraulic elevators. But climate control within the structures was still through natural ventilation.

A major invention was the foundation system for the high rise. The traditional spread or step footing was not feasible due to large loads generated by the high rise. The caisson foundation was developed. It consisted of a cylindrical shaft braced with board sheathing which was hand-dug to the bedrock and then filled with concrete to create a "column" to take the loads of the building on top.

In the years after World War II, glass was used extensively in high rise structures, culminating in the curtain-walled skyscraper. But the efficiency of such high rise structures was possible only after the development of rubber as a sealant, artificial climate control, and through the use of aluminum as a building material. One of the major landmarks in curtain walled structures was the United Nations Secretariat Building (1949) in New York City.

Go To Page: 1 2 3

Articles in this Topic    Discussions in this Topic