The tallest skyscraper in the world is the Burj Khalifa located in Dubai, United Arab Emirates. It stands 2,717 feet tall with 160 inhabitable stories and took over 6 years to construct from 2004 to 2010. Skyscrapers require strong foundations built on bedrock to support their massive weight. Their frames are constructed from steel columns and girders, with curtain walls on the exterior. To further spread the weight and stabilize tall buildings, skyscrapers are given spread footings and tuned mass dampers minimize swaying in the wind. During earthquakes, flexibility and damping systems help skyscrapers absorb shocks to avoid damage compared to more rigid designs.

1. Skyscrapers
Construction Technology

2. What is the tallest skyscraper?
Burj Khalifa
(Burj Dubai)
Location: Dubai, United Arab Emirates
Stories:160 Inhabitable + 46 Maintenance
Overall Height: 2,717 ft
Highest Point of Occupancy: 2,038 ft
Began: 2004
Completed: January 2010
Elevators: 57 (40 MPH)
Architect: Adrian Smith
Cost: 1.5 Billion
Over 2000ft. high!!

3. Foundations
Skyscrapers are very heavy, therefore we
need to have a solid foundation. Why?How do we stop this from happening?
Start on
BEDROCK!

4. Framing
Skyscrapers are framed using steel columns and girders.
The outer covering is called a curtain wall.

5. Spreading the weight
Even though the foundation has started on bedrock, we still
need to spread the weight; just to be safe.
How can we do this?
Typically, they use SPREAD FOOTING.
Spread Footing

6. Wind
Most skyscrapers sway in the wind.
How can we minimize the
distance of the sway?
Engineers use TUNED-MASS DAMPERS.
1. A computer detects how far the wind is making the
building move in one direction.
2. The computer will move a very heavy weight in the
opposing direction.
3. Within under a minute, the sway is minimized to a safe
level.

7. Tuned-Mass Damper
Notice the
size
compared
to the guy!!

8. Earthquakes
Many skyscrapers are built in cities that have fault lines underneath.There have been many disasters due to earthquakes.

9. How do we minimize damage?
We use damping systems!
Skyscrapers are built a little more flexible.
Flexibility allows the structure to twist and turn a
little without breaking and/or crumbling.
If the skyscrapers were rigid, pieces would snap off
easily in an earthquake.
ALSO…
What effects do you think this has on
the overall design?

10. Also…
Glass is attached using rubber channels.
This allows the glass to move a little bit. It has
a lower change of breaking in an earthquake.

11. For Extra Support
Cross-bracing is sometimes used.
Most of the
weight is
transferred
to the center
supports.
Most of the
weight is
transferred
to the outer
supports.
What kind of
cross-bracing
should be used for
this skyscraper?

12. First and Oldest
First skyscraper
Home Insurance Building
Location: Chicago
Height: 138 feet
Stories: 12
1885-1931
Oldest Still Standing
Milwaukee City Hall
Location: Milwaukee
Height: 353
Stories: 15
1895 - ?