The Capital Gate building in Abu Dhabi is 160 meters tall and leans 18 degrees to the west, making it the furthest leaning man-made tower in the world. It took two years and 600 laborers to construct the 53,100 square meter building out of reinforced concrete and steel at a cost of $233 million. The unusual leaning structural system uses a central concrete core surrounded by steel diagrid frames and horizontal outriggers to resist wind loads and maintain stability despite its irregular shape.

1. Special topic in structural Engineering
Capital Gate Abu
Dhabi
Bara AlRefai
United Arab Emirates University

2. Capital Gate
❖ 160 m tall
❖ 35 stories
❖ Inclined 18 degree to west.
❖ Capital gate title four times
more than the Tower of Pisa.
❖ It got Guinness certificate for
furthest leaning man mad
tower.

3. Capital Gate
❖

4. Capital Gate
❖ Cost $233 million.
❖ 600 people labor force
participate in construction.
❖ Two year of constriction.
❖ Completed in 2011.
❖ Total Area :53,100 square
meter.
❖ Mainly used for hotel and
offices.

5. Structural system
❖ Concrete core surrounded by
two steel truss (diagrid
system).
❖ External and internal diagrid
system (lateral load resisting
system).
❖ Steel beam support concrete
floor & run between two diagrid
system.

6. Structural system
❖ Outriggers are horizontal trusses
connect building core distant
structural element.
❖ Used to increase strength and
overturning stiffness.
❖ The dense outriggers system
started to be used from17th
mechanical floor.
❖ Mainly used to resist wind load.

7. Foundation
❖ Rectangular raft footing.
❖ 2 m depth and 7000 cubic
meter reinforced concrete.
❖ 490 piles.
❖ Each has 1 m diameter.
❖ Half under compression with
depth of 20 m.
❖ Other half under testation with
depth of 30 m.

8. Loads calculations
❖ Source:
❖ https://sites.google.com/site/gr
oup5capitalgate/structure/i-
analysis-and-description

9. Irregularity that Should be taken in
consideration
❖ The flowing Vertical
Irregularities that may exist in
Capital Gate Abu Dhabi :
1. Stiffness irregularity.
2. Mass irregularity.
❖ The flowing plan Irregularities
that may exist in Capital Gate
Abu Dhabi :
1. Torsional irregularity.
2. Diaphragm Discontinuity.
3. Out-of-plane Offsets of vertical
Element.

10. Thank You

11. References
❖ www.rmjm.com/the-architects-perspective-the-capital-gate
❖ www.e-architect.co.uk/dubai/capital-gate-abu-dhabi
❖ www.economist.com/blogs/dailychart/2011/10/leaning-
buildings
❖ www.slideshare.net/nayanrao1/seminar-on-capital-gate-
building
❖ https://sites.google.com/site/group5capitalgate/structure/iii-
drawings-and-diagrams
❖ https://store.ctbuh.org/PDF_Previews/Books/2012_CTBUHO
utriggerGuide_Preview.pdf