Capital Gate is a 35-storey tower in Abu Dhabi, notable for being the world's furthest leaning structure at an 18-degree angle. Completed in 2011, it houses the Hyatt Capital Gate hotel and 15,000 square meters of office space, all constructed using advanced steel diagrid technology and unique architectural design. The project has become a symbol of Abu Dhabi's progress and integrates with the Abu Dhabi National Exhibition Centre, enhancing its significance in the region.

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2. 1. INTRODUCTION
2. FACTS ABOUT CAPITAL GATE
3. STRUCTURAL ELEMENTS
 FOUNDATION
 CORE
 FAÇADE
 SUN SHADING
4. AMENITIES
5. PROJECT DATA
6. SUMMARY
7. REFERENCE
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3. • Capital Gate is the 35 storey focal point of Abu
Dhabi's capital centre
• Certified by the guinness book of records as the
farthest leaning tower
• Constructed with steel diagrid technology and
prestressed precambered elliptical core
• The tower is 160 meters high with a lean of 18
degrees i.e. 35 meters overhang and has a massive
eccentric deadweight
• Floors 2 to 16 accommodate commercial and office
space and the top floors accommodate the hyatt
hotel
• The tower has a organic shape which was inspired by
the wind shaped sand structures in the desert
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4.  The vertical and horizontal cross-sections of the tower are all unique
 Every one of the 12,500 panes of glass on the facade is a different size, although
each pane is triangular.
 The cross section of the tower changes from curved triangular to curved
rectangular as the tower progresses upwards
 The structure has two diagrid systems i.e. an external diagrid and an internal
diagrid which is linked to the central core with eight pin jointed structural
members
 The external diagrid comprises of 8250 members which are of different
thickness,length and orientation
 The project was completed within two years
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5. FOUNDATION:
 The foundation consists of a rectangular raft
footing supported on 400 concrete piles of 1
meter diameter
 Half of the piles are under compression and
run to a depth of about 20 meters
 The other half of the piles run to a depth of
about 30 meters and anchor tightly to the soil
and are in tension due to the massive eccentric
overhang of the building
 The 2 meter deep raft footing was made up of
7000 cum of reinforeced concrete to distribute
the loads evenly on the piles
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6.  The core was pre cambred meaning it was initially tilted
away from the overhang of the building and was
straightened by the dead load of the building
 The core was built using the technique called jump
forming
 The concreting was done at night to avoid the extreme
day heat which may cause the concrete to dry and crack
 Slump tests were carried out on evey batch of concrete
 Concreting was done by pumping and 250 mm slump
concrete was used
 The core was post tensioned
 A total of 146 tendons were incorporated into the core
through ducts
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7.  Each tendon was 20 meters long and splice overlap was upto 5 meters
 Pneumatic jack was used to stretch each tendon at a time
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8. FAÇADE:
 The façade /body was made up of steel cross
sections called cruciforms
 The external diagrid consists of 720 of such
cruciforms
 Each cruciform if having different
curvature,length and thickness
 The external cruciforms were made up of
600×600 mm hollow rectangular sections,the
thickness of the sections ranged from 80 mm at
the bottom to 40 mm at the top of the tower
 The internal diagrid cruciforms were made with
80 mm diameter hollow circular sections
 The dimensional accuracy +/- 1mm
 The floor height is 4 meters
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9.  The exterior is made up of 26000 triangular glass
panes called c240
 The glass panes consist of two silver coatings
 Each triangular glass pane has a unique shape
 18 triangular panes connected to each other by
hinge joints formed a diamond shaped panel
measuring 8×8 meters
 The diamond panels were connected to each
other by a two layer seal which made it water
proof and also allowed it to change shape
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10.  the top 18 floors houses an attrium which reduces
the eccentric weight of the building
 The internal diagrid support the weight of the 18
floors and is funnel shaped
 The internal diagrid is connected to the core by 8 pin
jointed structural members on the 18th floor also
known as mechanical floor
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11.  There’s a two storey extension cantelevered
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
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12.  The sun shading also known as the ‘splash’ starts from the 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 protects the building form direct sunlight and reflects upto 30% of
the incident radiation thus decreasing the air conditioning required
 The splash is supported by circular members which are connected to the
external diagrid
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1st floor plan 2nd floor plan
13th floor plan 15th floor plan

14. ELECTRICAL SERVICES:
 All common area lighting, power, two escape staircases and elevators are fed from the landlord’s
distribution network. One passenger elevator is backed up by standby generator power, for use in case
of emergency. All life safety systems and essential services are backed up by the standby generator. In
addition, some of the life safety system and essential system outlets are backed up by uninterrupted
power supply (UPS) to ensure availability of power at all times.
 The building is supplied at 11KV from an Abu Dhabi Distribution Company (ADDC) primary
substation and network to basement sub-station.
 Power is transformed to the operating voltage of 415 volts by five, 1,500KVA transformers installed in
the substation. Main distribution boards (MDBs) are fed from the transformers installed in the
basement low voltage (LV) switchgear room, adjacent to the substation. MDBs distribute power to the
development, through cable routes, rising bus bars, sub-main distribution boards (SMDBs) and
distribution boards (DBs).
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15. MECHANICAL SERVICES:
 Fresh air ventilation, fan coil unit (FCU) systems,fresh air handling units (AHUs), smoke extract
ventilation system, variable volume air-conditioning system, and chilled water (CW) system are
provided.The cooling requirement is served by TABREED district chilled water network, facilitated by
an energy transfer station at the basement and Level 1 of the building as the primary supply of chilled
water network consisting of two units of rated heat exchangers. The resulting or secondary chilled
water lines will be metered as being conveyed by four rated pumps serving AHUs and FCUs mounted
at all floors of the building.
PLUMBING:
 Sanitary wares, water tanks, domestic water systems, soil/waste/vent and overflows, irrigation system
and rainwater system have been included.
 The main source of the building’s potable water, from the ADWEA distribution line, is stored in a
tank at the basement floor, which undergoes a filtration system. The concrete water tank is a double
compartment type, allocated for domestic water, fire protection system, and irrigation source.Aside
from preliminary filtration, the domestic water passes through a proven anti-legionella chemical
dosing system. Water tanks are provided at basement, Level 1 and Level 17, with compliance to ADDC
requirements of minimum 2 days consumption storage.
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16.  Cost of the project was $233 million
 600 people labour force from different countries
 400 sub contractors
 Completion Date: 2011
 Height to Architectural Top: 165 meters
 Stories: 35
 Total built up Area: 53,100 square meters
 Primary Uses: Hotel/Office
 Project Developer: ADNEC Group
 Architect: RMJM
 Structural Engineer: RMJM
 MEP Engineer: RMJM
 Façade Consultant: Hyder Consulting
 Landscape Consultant: Al Khatib Cracknell
 Main Contractor: Al Habtoor Engineering
 Steel Contractor: Eversendai
 Façade Contractor: Waagner Biro
 Project Manager: Mace
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17.  September 2007 – work commences
 November 2007 – Pile driving starts
 April 2008 – Core wall construction starts
 February 2009 – Façade commences
 May 2009 – Reaches 100 m in height
 June 2009 – Incline starts to take shape
 October 2009 – Attains final height of 160 m
 December 2009 – Completion of exterior core structure
 January 2010 – First phase of splash completed
 February 2010 – Interior fit-out commences
 March 2010 – Commencement of link bridge to Abu Dhabi National Exhibition Centre
 April 2010 – Commencement of atrium roof
 2011 – Completed construction
 Opening date 21 Dec 2011
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18. While clearly a unique structure was built using some of the world’s most advanced
construction techniques, ADNEC believes the tower’s appeal goes far beyond an
architectural and engineering marvel.Functionality and purpose have been a prime
focus.Capital Gate houses Abu Dhabi’s first Hyatt Hotel, the five-star Hyatt Capital Gate, as
well as approximately 15,000 square meters of office space.The tower is also strategically
important to Abu Dhabi and visually represents the emirate’s progress and evolution. It is
the focal point of a world class business district, and is inter-connected with the thriving
Abu Dhabi National Exhibition Centre , which hosted more than 200 events in 2011,
welcoming around one million visitors. Capital Gate’s visitors or tenants have access to the
world-class amenities within the building as well as elsewhere within the ADNEC
development, including facilities such as a fully-operational airport check-in facility.The
Guinness world record for “world’s furthest leaning manmade tower” has shone a spotlight
on Capital Gate and Abu Dhabi, as has a “Megastructures” documentary on National
Geographic Channel (“The Leaning Tower of Abu Dhabi”), broadcast in more than 166
countries to an estimated television audience of more than 200 million.The people of Abu
Dhabi feel a sense of honor in Capital Gate. They are confident Capital Gate’s aesthetic
splendor and technical achievement will generate admiration and discussions around the
world for years.
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19.  www.wikipedia.com
 CTBUH Journal, 2012 Issue II
 CTBUH Journal, 2013 Issue III
 www.skyscrapercentre.com
 www.capitalgate.eu
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