ROBERTSON GEO
The Installation of 278 high-capacity (46-61 strand) post-tension anchors and relocation of the structural work platform mounted to the spillway where the work was performed. Rock anchors were up to 300ft in length.
The constant modification of the platform was completed to allow for the constant flow of work being completed at both platform elevation and below with the work platform supporting 80 ton cranes, drill rigs, and carry deck cranes.
The final row of anchors were drilled and installed from a floating plant located in the spillway and moored to the face of dam. These high-capacity anchors were installed through the concrete dam with embedded steel obstructions at varying depths through the dam down into bedrock consisting of interbedded layers of clay, shale and sandstone.
Project duration was from 2013-2019 and the High Resolution Optical Televiewer (Hi-OPTV) was logged on every anchor borehole prior to inserting the tendons to verify sound bond zone and no obstructions were encountered during drilling.