Though steel is a common building material, its origins are generally unclear. Many have heard of steel and know of several of its uses and applications but how it’s made or even what it is, is often disregarded. Steel is an iron and carbon alloy that contains trace amounts of other materials and elements such as silicon, phosphorus, manganese, sulfur, and oxygen. 1 Though steel is not a modern invention as many cultures have been producing some variation of steel since 200 BC, Henry Bessemer is often credited with the invention, or more accurately, the development, of the mass production of steel. A derivative of the original Bessemer Process of steel production is still used today. The process uses air to purify and oxidize the steel while it is in its melted form. 2 However, today, the contemporary method that is widely used is called EAF. EAF utilizes an electric arc furnace that melts down scrap steel and combines it with some additional materials to create the final product. 2 Overall, this method is preferred because it is easy, cost effective, and environmentally friendly due to its use of recycled steel.
The development and mass production of steel was an important milestone for modern architecture and architects. This innovation allowed for more architectural freedom and for new aesthetics to be realized. The increased structural integrity of steel allowed for taller and more abstract building designs. Examples of innovation through steel can be seen in modern examples, such as Frank Gehry’s Jay Pritzker Pavilion, as well as in early designs, such as Louis Sullivan’s Wainwright Building.
Frank Gehry’s Jay Pritzker Pavilion is located in Millenium Park, Chicago, Illinois. In the heart of downtown Chicago, the Pritzker Pavilion is a glittering mass of stainless steel, sprawled out among a jungle of skyscrapers. 4 The Pritzker Pavilion shows an innovative use of steel in its construction; by using the reflective nature of steel, Gehry effectively blends the structure into its surroundings and landscape (Figure 1). In addition, the integrity of the material allows for the steel trellises that encase the seating area to be thin bands rather than imposing beams. As seen in Figure 1, the steel trellises create an enclosed concert space yet contain the integrity needed to suspend heavy audiovisual equipment. This allows for the spectators to have an uninterrupted view of the city and skyline while still being able to enjoy the concert-hall quality of music being performed.
Similar to the Pritzker Pavilion, the successful use of steel in Louis Sullivan’s Wainwright Building is also due to the rigidity of the material. The Wainwright Building was built in 1892 in St. Louis, Missouri as an office building and one of the first skyscrapers of its time. 5 It is only through the use of steel can the height of the Wainwright Building be achieved. The emphasis on verticality, as seen by the uninterrupted vertical lengths on the facade, further iterates the height of the building (Figure 2). The building is able to achieve this height only through the innovative use of a steel frame. 6
Figure 1: Jay Pritzker Pavilion (1999-2004), Chicago, IL. Frank Gehry. Photographer: Jennifer Xu.
Figure 2: Wainwright Building (1892), St. Louis, Missouri. Louis Sullivan. Photographer: J. Crocker, Wikimedia Commons. Link. (Accessed October 29, 2015)