Design of Dubai's record breaking 350m high twin triangular towers was based, in part, on geotechnical data gathered from three insitu site investigation techniques carried out by Costain Geotechnical Services.
Pressuremeter testing of the underlying weak calcareous cemented sediments was carried out, along with surface to borehole tomography in light of the anticipated high stresses that the structures would exert on the ground. Top drive rotary rigs drilled boreholes to depths of up to 83m. A biodegradable polymer flushing medium was used with rigid plastic liners and mylar sheeting to achieve the requirement for high quality core samples of the calcareous sediments.
Costain Geotechnical Services general manager Jim Cook said: 'Carrying out the site investigation provided a factual geotechnical report which gave parameters and geotechnical information on which the towers' foundation design was based.'
The towers form part of the prestigious Emirates commercial construction project and are supported with 200 bored piles of 47m in length.