Skyscrapers

 Skyscrapers are the world’s tallest buildings. They first appeared in New York and Chicago at the end of the 19th century. Skyscrapers are often like small cities. Theyoffer space for offices, apartments, shops, hotels, restaurants and other services. Tens of thousands of people live and work there.

 Building Skyscrapers

Skyscrapers have two parts: the foundation is the part below the ground and the superstructure is the part above the ground. Both sections hold the weight of the building.

A skyscraper needs careful planning before it can be built. First a big hole a few stories deep is dug into the earth. Sometimes thisfoundation reaches into solid rock. Then steel and concrete beams and columns are placed into it. They carry the weight of the superstructure.

When the foundation is finished cranes are used to raise a steel frame up into the sky. The pieces of this frame are bolted together. As it moves upward other workers lay floors and hang in the outside walls. The complete structure of the skyscraper must be finished before the inside systems can be installed.

A skyscraper must also be able to hold off strong winds. Modern buildings are able to swing a few metres in each direction, like a tree, without damaging the structure. Sometimes a steel core rises upwards from the inside of the building to give it better support.

Service areas

Corridors , staircases, elevators, heating systems, air conditioning and electrical systems belong to the most important inner elements of a skyscraper. Although the outside structure can be completed in a few weeks it may take years to finish the whole building.

Pumps bring clean water to all parts of the skyscraper, the drainage system carries away water and waste materials.

Air conditioning and heating systems control the temperature in the building the whole year round. Electrical systems provide power and communication throughout the building andwires carry electricity to each floor. Elevators are the most important systems of a skyscraper. They carry people up and down at speeds of up to 500 metres per minute.

History of skyscrapers

Two discoveries in the middle of the 1800s made it possible to build modern skyscrapers. Before the Industrial Revolution brick and stone walls carried theweight of buildings. Because each floor was very heavy it was impossible to build very high houses. In the middle of the 19th century steel became an important building material. This metal was strong and light. Architects could now construct asteel skeleton to support very tall buildings. Chicago’s Home InsuranceCompany Building was ten stories tall and the first skyscraper to use such a steelconstruction.

Skyscrapers would have been useless if people had to walk up and down many flights of stairs. In 1853 an elevator safe enough to carry passengers was invented by Elisha Graves Otis.

During the early 20th century the construction of tall buildings became very popular in big cities. Cities grew bigger as more and more people could live and work there. Tall buildings were also seen as a symbol of power and greatness. Thus, major cities, especially in America, fought for the tallest buildings in the world. For four decades the Empire State Building in New York was the world’s higheststructure. The 381 metre high landmark has 102 stories and was completed in 1932. The World Trade Centre, finished in 1973, became a symbol the city’s economic strength. Even though many New Yorkers did not like them at the beginning, they got used tothe “Twin Towers” in the middle of Manhattan. The destruction of the World Trade Centre in the terrorist attacks of 2001 hit the heart of the city.

Today the world’s tallest buildings no longer stand in America. Other countries, mainly in the growing regions of Asia, have entered theprestigious race for the tallest structures in the world. The 452 metre high Petronas Towers in Malaysia, completed in 1996, became the first skyscraper outside the US to climb the top of the list. The Taipei 101, at a height of 508 metres, is currently the tallestcompleted building in the world, but the Burj Dubai which is expected to be completed in 2008 or 2009 will be over 700 metres high.

As the race for the world’s tallest building continues most experts have different opinions on how tall skyscrapers can become. Some say building a 1000-metre high structure would be no problem with today’s technology; others think that we would need lighter, stronger materials as well as faster elevators to make this possible.

The world’s tallest structures

Burj Dubai

Burj Dubai is a super tall skyscraper that is currently being built in Dubai. When it is completed, it will be the tallest man-made structure ever built. At a cost of about 4 billion dollars the tower will symbolize Dubai as a world city.

The final height of the building is still a secret but it could have up to 160 storiesand reach a height of 800 metres. The foundation has been laid 50 metres into the ground.

The Y-shaped tower consists of stainless steel and glass. It rises to the sky insteps from the middle of a man-made lake. In Islamic architecture these stepssymbolize rising towards heaven.

Burj Dubai will have apartments, shops, swimming pools, spas and an observation platform on the 124th floor. It is also expected to have the first hotel owned by Italian’s fashion tsar Giorgio Armani.

A total of 56 elevators carrying 40 people each will be able to move passengers at 18 minutes/second, a new world record.

Burj Dubai and the area around it

Words

• although =while
• appear = show up
• beam = a long thick piece of metal that is laid horizontally
• billion = one thousand million
• bolt = to nail two things together
• brick = a hard block of baked clay used to make buildings
• century = a hundred years
• column = a long strong piece of metal that is put up vertically to keep up a building
• complete = finish
• concrete = a strong building material that is made by mixing sand, small stones, water and cement
• consist of = to be made of
• construct = plan
• continue = go on
• core = a hard part
• corridor = a long narrow hallway between rooms in a building
• crane = a large machine that can lift heavy things
• currently = at the moment, now
• damage = here: to make weaker
• decade =ten years
• destruction =to damage completely so that you cannot use it any more
• dig – dug =to make a hole in the earth
• direction =way, course
• discovery = when you find out about something that nobody knew before
• drainage system =when water or waste flows away
• economic =everything about buying and selling and business
• electricity =the power that is in cables; it gives you light and makes machines work
• elevator = machine that takes people from one floor to another
• especially =above all
• even though =while
• expect = to think that something will happen or take place
• flight of stairs = a set of stairs between one floor and the next
• foundation = the material that is put under a building to hold it up
• frame =structure made of metal or wood that is around an object
• get used to =to do something that is not new any longer
• heating =system for making a building or a room warm
• height =how high something is
• impossible = it cannot be done
• install = to build something and make it ready to use
• insurance =you pay money to a company; they will pay the costs if something bad happens to you or something you have is damaged
• invent = to design or make something new
• landmark = something that is easy to see and that helps you know where you are
• lay =put
• mainly = mostly
• major = important, big
• man-made = made by people , not by nature
• observation platform = a place very high up where you have a beautiful view of a city or the countryside
• offer = give
• opinion = what you think about something
• outside =outer
• place = put
• popular = liked by a lot of people
• possible = it can be done
• power = electricity
• prestigious =to be seen as one of the best or most important
• provide = give
• race = a competition to find out who or what is the best
• raise = put up
• reach = get to
• rise = go up
• secret = something that not very many people know about
• section = part
• services =the work you do for someone
• skeleton = structure , frame
• solid = very hard
• spa = a place where water has special minerals in it and where people go to become healthier
• speed =how fast something is
• stainless steel = a type of steel that does not rust
• staircase =set of stairs inside a building
• steel = a strong metal made out of iron that you can shape easily
• step =a piece of wood, metal or stone that you put your foot on when you go up or down
• story = floor
• strength =how strong something is
• structure = something that has been built
• support = to hold something up
• swing = to move from one side to another
• technology =the way of doing things with computers and new machines
• throughout = in the whole
• thus =therefore, that is why
• towards =in the direction of
• tsar = here: a very important person in a certain area
• useless = no good
• waste materials = things that people do not need any more
• weight =how heavy something is
• wire = very thin piece of metal that is used to transport electricity