Drilled Displacement Piles
Drlled displacement piles are a ground improvement system. DDP’s are displacement elements that are installed using a specially designed tool at the working end of a high torque drilling machine.
Diameters range from 300mm to 610mm.
Rig weights from 50 to 160 tonnes.
Depths up to 32 metres.
The DDP’s are well adapted to high surface loading conditions and strict settlement requirements and are used to support slabs-on-grade, isolated footings and embankments. The DDP technology is very well suited for very soft soil conditions such as organic clays, alluvial deposits and wastes.
DDP’s can also be used to directly support the loads imposed by the structure and to improve the global response of the soil in order to control settlement. The dimensions, spacing, and composition of the DDP’s are based upon the development of an optimal combination of support from the columns and the surrounding soil to limit settlement for the project within the allowable range and to obtain the required value for the equivalent composite deformation modulus of the improved soil. With the assistance of on board computers, the piles are built to a high level of quality.
- Increases the strength properties and modulus of the soil.
- Displaces soil laterally, with only 5-10% spoil, thus excellent method for contaminated soil.
- Reduces vibration and minimizes disturbance of the surface layer.
Scope of Works
Central Coast Highway / Manns Road / Brisbane Water Drive Intersections and Approaches Upgrade at West Gosford. Main construction of roadworks, bridgeworks and associated activities for the upgrade and involves the widening and realignment of Brisbane Water Drive and Manns Road between Kulara Avenue in the south and Stockyard Place in the north to form a single at-grade fully signalised intersection with the Central Coast Highway.
Scope of Works
Ground improvement of the Central Coast Highway between Erina Heights and Wamberal, 572No Drilled Displacement Piles 450mm dia; column depth from 5.0 to 14.1m; grid spacing: varies from 1.2 to 2.0m.
Royal Shores Ermington is a residential development project comprising of Lots 301-302, 303-304, 305 and 306. These lots will house medium rise buildings with two basement car parks. The sites are situated next to the Parramatta River and required 6.00 meters of excavation to create the basement structures.
Scope of Works
Avopiling was awarded the contract by Dasco Australia to design and construct the foundation piles and install sheet piles. Sheetpiles are double AZ20-700 to lengths ranging from 12 to 25 metres and with a total area of 15,000 square meters.
Foundation piles are mostly drilled displacement piles ranging from 450mmØ to 610mmØ to depths of 16.00 to 25.00 metres. CFA Piles 750mmØ and 900mmØ to depths of 22.00 meters and UC steel columns with lengths from 18 to 21 meters were also installed as part of the foundation piles.
Drilled displacement piles on crtical sections were subjected to PDA test and showed positive results.