Underground mining operations are inherently complex, involving a sequence of interdependent tasks where ground support plays a critical role in both safety and productivity. The efficiency of this process often hinges on how well individual support elements – scaling, reinforcement, material transport, and concrete application – function together as part of a cohesive system.
This article examines an integrated ground support approach through the lens of three machines designed to operate in sequence: a mechanical scaler, a concrete remixer, and a shotcrete sprayer. One implementation of this system – developed by Getman Corp. – includes the ProScale, ProMix, and ProShot platforms. By focusing on their complementary roles in the support cycle, this examination highlights how technical design and process continuity contribute to improved safety, reduced cycle time, and consistent material application in challenging underground environments.
Scaling as the foundation of ground control
Scaling is typically the first ground support task following drilling and blasting. Its primary objective is to remove loose or unstable rock from the excavation surface to create a safer environment for subsequent work. The performance of this step directly influences the effectiveness of subsequent support installation and overall heading stability.
The Getman ProScale system includes multiple models differentiated by scaling reach and heading compatibility:
- A compact unit with an effective scaling envelope suitable for headings up to 6x6 m.
- Two mid-sized models capable of scaling up to 7 and 8 m vertically and horizontally.
- A large-scale variant offering maximum coverage approaching 9 m, with boom extension capabilities up to 11.1 m.
All models employ single-extension telescopic booms that allow scaling advancement up to 4 m without repositioning. The operator compartment is positioned at the rear of the chassis to enhance safety by increasing the distance from the rock face. Features such as a slewing tool for full pass coverage, ROPS/FOPS-certified cabins mounted on vibration-isolating components, and emergency reversing capability support operator safety and productivity. Multiple tool configurations, including hydraulic hammers and rotary cutters, allow adaptation to varied rock formations.
By removing hazardous material prior to support installation, dedicated mechanical scalers contribute to injury risk mitigation and cycle time optimisation.
Transport and delivery of shotcrete materials
Following scaling, underground operations often require structural reinforcement and sealing of newly exposed surfaces. Rock bolting and meshing may precede shotcrete application, particularly in high-stress or fractured zones. Shotcrete (sprayed concrete) is commonly employed for surface stabilisation, and the logistical challenge lies in transporting the material from the surface batch plant to the application site while maintaining mix integrity.
This task is facilitated by dedicated remixer vehicles. The Getman ProMix system includes various drum sizes and configurations, including horizontal remixer drums and agitator-style drums. Drums incorporate internal helical vanes to maintain homogeneity during tramming and discharge. Hydraulic lift cylinders allow the discharge cone to be adjusted to accommodate shotcrete hopper height and heading conditions. The drum tilt system allows the discharge neck of the drum to clear the lip of the hopper on uneven ground.
This is a preview of an article that was originally published in the May 2025 issue of Global Mining Review.
Subscribe to Global Mining Review for free to read this article in full and many more here.