Resultados
Delivered a coordinated design-and-construct ground support package, stabilising the rock face surrounding the portal, addressing loose rock hazards above the existing portal structures.
Maintained ongoing mining operations within the decline pit, with construction access and exclusion zones arranged around operational vehicle movements.
Improved drilling efficiency through the use of the HRD, reducing the duration of anchor installation and associated disruption to mine activities.
Completed the reinforced shotcrete retaining wall around the existing portal, providing an engineered ground support solution suited to the mine's operational requirements.
Solución del proyecto
Combined rope access and elevated work platforms to undertake initial hand scaling, removing loose rock from the west and north walls and clearing vegetation approximately 15 ft behind the slope crest.
Deployed high reach drill to install ground anchors, using continuous air flushing during open-hole drilling before grouting the anchors.
Completed verification anchor testing and proof testing to confirm ground capacity and installed anchor performance before progressing with the reinforced facing.
Installed steel mesh and horizontal reinforcing bars across the treatment area, connecting the reinforcement to the anchor heads to form the retaining wall system.
Applied wet-mix shotcrete using an experienced nozzle operator working from an elevated platform, constructing the reinforced facing around the portal and extending to the slope crest.
Coordinated access arrangements and exclusion zones with mine personnel to allow continued dump truck movements during construction.
Desafíos del proyecto
The steep rock faces surrounding the mine entrance required safe access for scaling, drilling, reinforcement installation and shotcrete application at varying elevations.
Existing portal canopies and structural elements restricted equipment positioning and required careful planning to complete works around the entrance without damaging infrastructure.
Construction activities needed to accommodate ongoing dump truck movements within the decline pit, requiring managed exclusion zones and coordination with mine operations.
Loose rock, vegetation and accumulated debris presented hazards during initial face preparation, particularly above the existing portal canopy.
Drilling, anchor testing, reinforcement handling and shotcrete application required careful sequencing to maintain safe working conditions around the operational entrance.
Descripción general del proyecto
Geovert was engaged to undertake the design and construction of an anchored reinforced shotcrete retaining wall around an underground limestone mine portal in Nebraska, USA. The project combined maintenance scaling and vegetation removal along the west and north rock walls. Working around existing portal structures and ongoing mine operations, Geovert delivered the ground engineering package from initial face preparation through to anchor installation, reinforcement and shotcrete construction. The works required adaptable access methods and close coordination with mine personnel to maintain operational access throughout the program.