Name: Morar RóbertAcademic Year: 2011-2012Presentation Date: 21.12.2011

History of Technics – Presentation Summary

TITLE: THE EMPIRE STATE BUILDING

I. Planning and design

The Empire State Building was the highest building in the world for forty Years with a height of 448 metres. It was constructed in New York (USA) in an era when American cities such as Chicago and New York competed to have the highest skyscrapers.

To make way for the new skyscraper the old Waldorf-Astoria Hotel on Fifth Avenue was demolished. Demolition started in March 1930 and the construction of the new building was completed in fourteen months, on May 14th, 1931.

With a 102 stories it was the tallest building in the world for forty years. Only when the first tower of the World Trade Centre was completed in 1972 was it deposed as the highest building. Today it stands as the tallest building in New York City, a sad, but defiant, reminder of the World Trade Center tragedy. The Empire State Building is currently the third tallest skyscraper in the United States and the 15th tallest in the world.

The Empire State Building was designed by William F. Lamb from the architectural firm Shreve, Lamb and Harmon, which produced the building drawings in just two weeks, using its earlier designs for the Reynolds Building in Winston-Salem, North Carolina, and the Carew Tower in Cincinnati, Ohio (designed by the architectural firm W.W. Ahlschlager & Associates) as a basis. The building was designed from the top down. The construction company was chaired by Alfred E. Smith, a former Governor of New York and James Farley's General Builders Supply Corporation supplied the building materials. John W. Bowser was project construction superintendent, while structural engineer was Homer Gage Balcom.

Unlike most of today's skyscrapers, the Empire State Building features an art deco design, typical of pre–World War II architecture in New York. The modernistic stainless steel canopies of the entrances on 33rd and 34th Streets lead to two story-high corridors around the elevator core, crossed by stainless steel and glass-enclosed bridges at the second-floor level.

The building has 113 km of pipe, 760,000 m of electrical wire. As for the illumination, the color of the building’s lights changes according to current events. In 1964, floodlights were added to illuminate the top of the building at night, in colors chosen to match seasonal and other events, such as St. Patrick's Day, Christmas, Independence Day. It is heated by low-pressure steam; despite its height, the building only requires between 14 and 21 kPa of steam pressure for heating

II. Construction characteristics

The ESB can boast about some impressive dimensions. As mentioned before, it is 448 m high, and 381 m without the antenna spire on its top. The area of site covers 7,240 m2, while the total floor area in the building is 257,211 m2. The foundation is based 16.7 meters below ground level.

In its day, the Empire State Building was constructed using up to date technology. A substantial concrete base was laid as a foundation to take the weight of the steel framework of the building. All the steel sections were prefabricated, that is, manufactured in a steel mill and transported to the construction site. The sections were manufactured to exact sizes to within 2mm tolerance and prepared so that they could either be bolted together or joined with rivets. The total weight of the building is approximately 340,000 t. The exterior of the building was built using Indiana limestone panels.

The labourers (sky boys as they were called), walked up and down the structure as it was put together, their job being to fix the separate sections together, often using large nuts and bolts or hot rivets. The second technique was first used in the ship building industry as a method of joining large steel plates. The steel rivet is heated until the plain end is red hot. It is then passed through the holes of the two sections. When hot the rivet is soft and can be shaped using a special rivet gun which rounds the plain end so that it is permanently fixed in position.

It only took three days for the sections to be manufactured in the steel mill, transported and positioned in the framework as part of the buildings structure. Once the steel framework was fixed in positioned it was then finished with an outer skin of stone. While the project was considered very safe for the era and complexity, six workers died.

The Empire State Building is a reinforced masonry structure in which the structural steel beams are encased within limestone walls or slabs of concrete 20 cm thick. This heavy mass provides exceptional fire protection that insulates the steel within from excessive heating. The Empire State Building is also a heavily compartmented structure. Each floor is self-contained with its own independent heating and cooling ducts, elevator and utility shafts are surrounded by thick masonry walls, fire partitions separate each floor and rooms within each floor, and the fireproof stairway prevents smoke from rising to upper stories. These features make it very difficult for fire to spread beyond a limited area. For these reasons, the Empire State Building is still considered one of the world's safest skyscrapers in a fire.

The Empire State Building is a braced frame steel construction, which makes it quite rigid. It should be of higher strength than residential buildings. Also steel constructions do not degrade over time as concrete ones do, plus it has been well maintained, in comparison to residential buildings of similar age. Moreover, New York is a low seismic activity zone. The last major earthquake was a M5 (5 Richter) in 1884, in which no building collapsed. A M6 earthquake may happen once every 500 years and a M7 once every 2500 years. In conclusion, the ESB should not be threatened by earthquakes. The ESB was also a subject of several wind load studies. The skyscraper's foundation acts as an effective anchor to keep the building from tipping over in high winds: it would take an estimated 4.5 million pounds of wind pressure to blow it over.

III. Costs: construction and service

The Empire State Building cost $40,948,900 to build (equal to roughly $500,000,000 in 2010). Long-term forecasting of the life cycle of the structure was implemented at the design phase to ensure that the building's future intended uses were not restricted by the requirements of previous generations. This is particularly evident in the over-design of the building's electrical system. Some referred to the building as the building that should never had been, due to the huge costs. It requires 150 maintenance people and produces around 100 tons of trash a month. Today, due to recent renovation service costs are relatively low.

IV. Durability and sustainability aspects

A modeling and analysis project has been completed which will save 38 percent of the building's energy and $4.4 million annually. ESB is currently undergoing a $550 million renovation, with $120 million spent in an effort to transform the building into a more energy efficient and eco-friendly structure. The ESB received a gold Leadership in Energy and Environmental Design (LEED) rating in September 2011, being the tallest LEED certified building in the United States. The Empire State Building is an iconic building: it has been, is, and probably will be well maintained in order to ensure its durability for as long as possible.

V. Image gallery

The Empire State Building under construction

The interior and exterior of the Empire State Building todayVI. References

http://www.technologystudent.com

http://science.howstuffworks.com/engineering/structural

http://en.wikipedia.org

http://www.esbnyc.com

http://www.aerospaceweb.org

http://digitalgallery.nypl.org

Tauranac, John (1995). The Empire State Building: The Making of a Landmark.