Palm island

Detail content about construction of breakwater.

1. PALM ISLANDS Presented by: Rohan KUMAR (802023014)

2. INTRODUCTION: The Palm Islands are an artificial archipelago in Dubai , United Arab Emirates on which major commercial and residential infrastructures will be constructed. They are being constructed by Nakheel Properties, a property developer in the United Arab Emirates. The islands are the Palm Jumeirah , the Palm Jebel Ali and the Palm Deira .

3. THE PALM JUMEIRAH Project Name: The Palm Jumeirah . Location : Jumeirah Coastal Area, Dubai, UAE. Project Area: 2,209 sq miles. Construction Date: 2001 Client : Nakheel . Palm Jumeirah is one of the largest artificial islands in the world. The project aim was to increase the limited space for beach-front properties by adding 78.6km to the city’s current 72km.

4. The unique shape is culturally relevant & significantly symbolic to the region Consists of 2 parts: - BREAKWATER FORM – Acts as a barrier to the sea protecting the inner palm from wave action & water flow. - THE PALM – consists of a main trunk & 17 fronds for residential & commercial space .

5. CONSTRUCTION STEPS Estimation of WAVE STRENGTH. Construction of BREAKWATER. SAND FILLING and COMPACTION. Construction of BUILDINGS.

6. Estimation of WAVE STRENGTH To estimate the strength of the waves, r esearch team worked out that Arabian gulf and declared that Breakwater has to be constructed having height up to 3 m & 11.5 Km long.

7. Construction of BREAKWATER Dredgers would collect sand from the sea and dump it where break water was to be constructed. For the construction, 5.5 million cubic meter of rock was needed. They were taken from quarries of UAE . Each piece of rock weighed about 6 tons which is excavated from 16 quarries across UAE.

8. SAND FILLING & COMPACTION 94 million cubic meter of sand was needed for the construction of this island .

9. In the case of sand filling, the sand was just sprayed but not compacted, then first Roller compacting was used but later earthquake effect were considered and then Vibro Compaction method was used.

10. Construction of BUILDINGS By march 2004, Phase 1 was finished and by 2006 the whole construction of the buildings must be done. Before it was estimated for 60,000 people but later it was made double because of demand.

11. BREAKWATER The crescent breakwater is approximately 11 km long and 200 m wide and will be used as a recreational island itself .

12. C ross section

13. To stabilize the inner layer. Fibertex Geotextiles is designed to retain particles while allowing free movement of water. Migration of layers is avoided and the load-bearing capacity is maintained. Geotextile functions;

14. P rocess For the breakwater crescent to be functional along the 5 km radius of Palm Jumeirah , it had to be at least 3 m above waves. This project required 9 barges, 15 tugboats, 7 dredgers, 30 heavy land-based machines, and 10 floating cranes. The company that constructed the breakwater crescent was   Archirodon Overseas.  The islands themselves would be made out of an obscene amount of sand dredged from three massive barren sea beds nearby (from the gulf), while the breakwater crescent out of rock and sand, though mostly rock . The bottom sand layer of the crescent breakwater is 7.4 m thick. The challenge of dumping this sand layer was that it had to be done when the sea was the calmest to ensure stability.

15. Then, barge-loads of rubble were dumped on top of the sand layer to raise the breakwater crescent from 4 m below to approximately 4 m above the sea . Sloping layers take out force of waves as it comes into contact with the walls . Since, sand and rubble are the base of the breakwater crescent, how does the breakwater actually protect the islands ? - The real protection comes from the outer armor . Now, A nother question arises that how this stone wall is expected to stay in place without concrete to secure it ? - Interlocking.

16. Challenges Dubai’s desert sand is not suitable for constructing island. Its particles are too fine and won’t stick together firmly and will be easily washed away. The best sand was found 6 nautical miles(11 km) out of sea. Dredgers scoop up 8000 ton of sand less than an hour and spray the sand into the place. The process is called rain bowing . But it was difficult to say that sand was falling at right place. It was achieved by GPS technology. 

17. The water inside the sea wall (break water) was not circulating resulting in dirty water being stored inside .

18. The sand island must support an entire city on it . But sand is not an easy platform to build on. Because the sand sprayed is loose and not compactable. - The solution was to use process called vibro - compaction . The shafts of vibro – compacting machine vibrate shaking the ground around it and compact the land.

19. V ibro – compaction. Reduce foundation settlement Increase bearing capacity . Increasing stiffness. Increasing sheer strength. Reduce permeability. Mitigate potential for liquefaction. Provide slope stabilization.

20. B uilding massive structure on shore line resulted in change in shape of shore line so, at some place shore will extend and other place it will erode.   Beach Erosion;

21. M easure to protect the coast C oastal monitoring program. By studying the baseline (measurement of depth of water in oceans) and topographic survey of the Jumeirah coastline. S ediment sampling and analysis. By using  Acoustic Doppler Current Profiler (ADCP) equipment.

22. Conclusion Installation of utilities and pipelines was very difficult and laborious . To counteract with the waves and the constant motion of the sea,  breakwater  were built all around the island . Shape of the island was monitored using the global positioning system . A Vibro -compaction technique played a vital role in preventing the liquefaction and to hold the island's base together to make a strong foundation for further construction . The theory of Ocean colonization was taken in consideration to extend society territory to  the ocean   by permanent settlement floating on the ocean surface by doing   offshore construction.

23. References http://engineeringchallenges.blogspot.com / https://www.azobuild.com / https://adventure.howstuffworks.com / https:// sites.google.com/site/palmislandsimpact/general-information/construction-of-the-islands https:// studentshare.org/other/1416181-major-engineering-challenges-faced-in-palm-island