Dubai: Readymix concrete maker Unimix has made history by setting a world record for the highest single-stage pumping of concrete on May 13, the company said in an e-mailed statement yesterday.
“The previous record of 448 metres set at the 508-metre-high Taipei 101 building in Taiwan was surpassed by Unimix when Grade 80 MPa HPC was pumped vertically to a height of 452 metres at level 126 of the Burj Dubai,” the statement said.
A significant aspect in the Burj Dubai pumping operation is that a very low water-cement ratio, high-strength concrete mix was pumped single-stage to this new record height.
Low water-cement ratio mixes are the most difficult to pump.
“As for Unimix, this is a record-breaking feat for Putzmeister as well, as the pumping operation was successfully accomplished with the help of the super high pressure Putzmeister BSA-14000 SHPD pumps,” it said.
“To date, Unimix has supplied more than 305,000 cubic metres of high-performance concrete (HPC) mixes for the Burj Dubai project.
HPC mixes are the preferred choice of clients since they provide both very good flow characteristics and high strength, thus making it highly beneficial for easy consolidation.
“The concrete in the Burj Dubai structure can easily be claimed to have the best and close to perfect consolidation and finish, thanks to the excellent placement methods employed by the main contractor, Samsung-Besix-Arabtec JV.”
The Burj Dubai has reached a height of 452 metres. The final height of the tower remains a closely guarded secret.
However, it will be the world’s tallest tower upon completion at the end of 2008.