- Providence, USA
- PBA 928
As part of the New district Plan prepared by the Rhode Island Department of Transportation, in 2003 constructions starts to build new ramps to improve the access to the Washington bridge.
DDC’s help was invoked because the traditional methods for extraction the mud and heavy clay from the 14 steel foundation casing were found unsuitable. The job was executed with the Wirth PBA928 top drill rig.
Mud and clay are easily removed with the reversed airlift drilling principal. For environmental reasons the mud-clay-water solution was collected in large containers where they could settle.
After removing the mud and clay the piles were drilled 2m to 7,5m deep into the bedrock. While drilling into the bedrock the casing moved along with the PBA928 on top of it.