Ahead of the commencement of the civil infrastructure construction, it was critical to improve the technical characteristics of the reclaimed land.
Given the 2006 completion date and to speed up the natural process of sand consolidation and mitigate any risk of liquification – in case of sudden movement of Earth’s crust at tectonic plates boundaries’ line – the sand underwent a process called vibro-compaction.
Palm Jumeirah’s induced settlement by
vibro-compaction could have taken decades if it
were left to occur naturally
Vibro compaction on Palm Jumeirah started in March 2004. The first uses full water pressure on an oscillating vibrator to penetrate to the required depth. Then compaction is carried out in steps from the maximum depth of penetration upwards. It encompasses a cylindrical soil body of up to five metres in diameter. The increase in density is indicated by an increased power consumption of the vibrator. At this stage, an immediate settlement at the surface would be noticeable, and that requires backfilling.
During this process the sand in the crater around the vibrator is filled with imported or existing sand. During the final step, the surface is re-levelled and compacted with surface rollers. The vibrating props would penetrate points fixed on the ground drawing a complex pre-determined grid following a geotechnical study based on soil campaign test results. In total, fifteen cranes were used in drilling 200,000 holes 12 m into the reclaimed sand.
Following the completion of vibro-compaction, the architecture, urbanism and building construction works could begin.
