Capital Gate is a 160m tall skyscraper in Abu Dhabi that leans 18 degrees westward, making it the furthest leaning man-made tower in the world. It was constructed between 2007-2011 and required advanced engineering techniques due to its unusual shape, including a pre-cambered core to counteract the building's tilt. Capital Gate houses offices and the Hyatt Capital Gate hotel, and its unique design has broken several world records.

1. CAPITAL GATE –ABU DHABI
MOST INCLINED TOWER ON THE PLANET

2. CONTENT
• General description
• Introduction
• Architecture
• Soil type
• Structure
• Foundation
• Core
• Façade
• Sun shading
• Floor system
• Fire proofing
• Thermal system
• Sustainable strategies
• Conclusion
• References

3. GENERAL DESCRIPTION
• Type - Commercial Offices; 5 star hotel
• Location - Abu Dhabi , United Arab Emirate
• Construction - started- Sept 2007
- completed-2011
• Owner - Abu Dhabi National Exhibition
Company(ADNEC)
• Height roof - 160 m (520 ft)
• Floor area - 53,100m2(572,000 ft)
• Floor count - 35
• Project developer -ADNEC Group

4. • Architect -Robert Mathew , Johnson-
Marshall and partners(RMJM)
• Main contractor - Al Habtoor Engineering
Enterprises
• Inclination - 18 degree westward
• Project Cost - $231m
• Steel Contractor - Eversendai
• Project Manager - Mace

5. INTRODUCTION
• CAPITAL GATE is one of the tallest skyscraper in Abu
Dhabi(160m).
• Tilting 18 deg westward(over four times as much as
Pisa).
• 35 storey structure includes a cantilevered tea lounge,
open air pool deck and Abu Dhabi’s 1st Hyatt hotel.
• It was the first building in the world to use a pre-
cambered core, with a built in lean of 350mm
engineered to straighten with the addition of the upper
floor.
• Also the 1st to use vertical post-tensioning of the core.

6. • It has 30 meeting rooms ,conference facilities for
1,200 people, a business center on the ground floor,
a helipad and an eight outlet food court.
• The $231m project was developed by Abu Dhabi
National Exhibitions Company.
• Construction work- Sept 2007-2011. Commercial
leasing of tower began in April 2011.
• In Sept 2011 , the project won the Best
Commercial/Mixed Use and the Best Overall Project
of the Year at 2011 Cityscape Global Awards for
Architecture in Emerging Markets.
• The Guinness Book of World Records certified
Capital Gate as ” World’s furthest leaning man-
made tower”.

8. ARCHITECTURAL EXPRESSION
• The ground-breaking form of Capital gate is
due not only to its lean, but also to its funnel
shape.
• The façade glazing emphasizes the organic
elements with diagonals spiraling up along the
structural diagrid.
• The potentially monument scale of Capital
Gate is tempered by a sun shading on south
façade known as splash.
• Due to its unique shape the upper half of the
tower widens to create an atrium at the hotel’s
guest room floors.

9. The atrium is funnel shaped and appears carved out of
the solid form around it, spiraling and leaning along
the tower.
Hotel atrium , looking up

10. SOIL TYPE
• The construction of building has been done on
the sea shore.
• The sea shore contain more of sand content, the
strength is gained by 30 m steel rods vertically
drilled deep into the ground.

11. STRUCTURE OF THE TOWER
• The tower has a 2-layer design. The central core of the
tower built leaning in the opposite direction to the
inclination of the building and straights with height.
• Advanced diagrid technology has been adopted for
the buildings twisted design.

12. • Steel beam support concrete floor & run b/w two
diagrid system.
• Outriggers are horizontal trusses connect building
distant structural element.
• Used to increase strength& overturning stiffness.
• The dense outriggers system started to be used
from 17th mechanical floor.
• Mainly used to resist wind load.

14. FOUNDATION
• The foundation consist of
rectangular raft footing on 490
concrete piles of 1m diameter.
• Half of the piles are under
compression and run to a depth
of 20 m.
• The other half of the piles run to
a depth of about 30 m and are in
tension due to massive eccentric
overhang of the building.

15. • The 2m deep raft footing was made up of
7000m3 of reinforced concrete to distribute
the loads evenly on the piles.

16. •

17. THE CORE
• The core was pre cambered i.e. it was initially tilted
away from the overhang of the building.
• The core was built using the technique called jump
forming(climbing formwork were used).
• The concreting was done at night to avoid the
extreme day heat.
• Slump test was carried out at every batch of
concrete.
• Concreting was done by pumping .
• The core was post tensioned.

19. • The core contains 15,000m3 of concrete
reinforced with 10,000tonnes of steel .

20. FACADE
• The façade/body was made up of steel cross
sections called cruciforms.
• The external diagrid consist of 720 such cruciforms.
• Each cruciform were different in length, curvature
and thickness.
• The external cruciforms were made up of
600x600mm hollow rectangular sections , the
thickness of the section ranged from 80mm at the
bottom to 40 mm at the top of the tower.
• The internal diagrid cruciforms were made with 80
mm dia hollow circular sections.

21. • The dimensional accuracy +/-1mm.
• The floor height is 4 m.

22. • Capital Gate’s cladding consist of two distinct
elements-a curtain wall glazing system and a metal
mesh shading system.
• The curtain wall consist of diamond shaped panels
stacked up floor by floor.
• The steel framing used was manufactured in
Austria. Frame profile is triangular to take loads in
all direction.
• The glass used is a low emissivity glass, very
transparent, yet provide good thermal insulation
and glare reduction.

23. • There’s a two storey
extension cantilevered
12 meters from the
tower.
• They are braced to the
external diagrid with
circular steel members
which reach diagonally
down to the
mechanical floor.
• The extension houses
a swimming pool.

24. SUNSHADING
• The sun shading starts from 18th floor and extends to
the Abu Dhabi National Exhibition Centre Grandstand.
• It is made up of steel members interlocked to form a
mesh.
• The splash reflects upto 30% of the incident radiation
thus decreasing the air conditioning required.
• The splash is supported by circular members which are
connected to external diagrid.

25. They are braced to the external diagrid with steel profiles
reaching diagonally to the plant floor.

26. FLOOR SYSTEM
• The floors are constructed using a composite
system, spanning from the main core, to the
internal diagrid and between internal and external
diagrid.
• The floor beams are connected to the concrete core
via embedment plates cast directly into the core
wall when concrete is poured.
FIRE PROOFING
• Fireproofing is done by installing steel fireproofing.
• It was done by PFP contracting.

28. WATER /VAPOUR
• The ‘pressure plate’ system used that has been
developed for the steel frame guarantees the water
tightness of the façade and allows thinner panes of
glass to be used , thereby reducing wt. of the
glazing system.
THERMAL
• The glass used on the tower’s façade is energy-
efficient containing two layers of silver inner coating
allowing a high degree of natural light permeate.
• It’s designed to keep the inside of building cool and
eliminate glare, while maintaining transparency of
the façade.

29. SUSTAINABLE STRATEGIES
• The round perimeter encloses space more
efficiently than a rectangle, so less façade surface is
needed. This is reduction in concrete, steel and
glass.
• Landscaping around capital gate creates a vegetated
roof over the basement increasing the thermal
insulation.
• The double-glazed façade is used to achieve greater
efficiency.
• Waste water is pre-cooled in b/w inner and outer
façade thereby reducing the energy consumptions
of the building by recycling the used air.

30. • Native plants are used which require less
irrigation.
• To further reduce potable water use in this
desert context, low-flow water fixtures are
installed in public areas and washrooms,
including WCs and faucets.
• District cooling is provided by Abu Dhabi
Municipality, a more energy-efficient means of
obtaining chilled water than installing chillers on
site.
• The chilled water is distributed by variable speed
pumping, which reduces energy use in operating
the air conditioning.

31. • Double skin façade system reduces the temp.
inside the building hence reduce the
requirement of air conditioning.
• The aloft building, another hotel located in
the compound , is tied into a total pf 560 solar
panels installed on the roof of ADNEC Park A,
covering an area of 2300sm that provides
90%of hot water supply.
• This saves an estimated 870 mega watt hours
of electricity per year and supplies hot water
to kitchens, hotel rooms and pool.

32. SCHEDULE
• It was delayed by 5.5months because of unexpected
excavations and piling restrictions due to nearby main
sewage line.
• There were more than 1,200 workers on site.
FINAL TIMELINE:
• Sept 2007-enabling works commence
• April 2008- core wall construction starts
• Feb 2009 – façade work commences
• May 2009 –Capital Gate reach 100m ht.
• Oct 2009- attains final ht. of 160m
• Dec 2009- completion of exterior core structure
• Feb 2010 – interior fit-out commences

33. • March 2010- work on link bridge to Abu Dhabi
National Exhibition center begins.
• April 2010 – work of atrium roof begins
• 2011- Construction work completed
• 21st Dec 2011- Opened

34. CONCLUSION
• While clearly unique structure was built using some
of the world’s advanced construction techniques.
• Functionality and purpose have been a prime focus.
• Owned and developed by ADNEC , Capital Gate is
the ultimate business capital in UAE.
• With far reaching views across Abu Dhabi and the
Arabian gulf , the tower accommodates approx
15,000sqm of exclusive office space as well as the
5star ‘Hyatt Capital gate’ hotel.
• The tower visually represent the Emirate’s progress
and evolution.
• It is focal point of a world class business district.

35. • It is interconnected with Abu Dhabi National
Exhibition Centre, which hosted more than 200
events in 2011, welcoming around one million
visitors.
• It has a “ Megastructures ” documentary on Nat
Geo channel ,broadcast in more than 166 countries.
• The Guinness Book of World Records certified
Capital Gate as ” World’s furthest leaning man-
made tower. It has shone a spotlight on the tower.

36. REFERENCES
• www.capitalgate.ae
• www.scribd.com
• Global.ctbuh.org
• www.designbuilt-network.com