Mining Project: Ground Control Safety for Deep Vein Mines

Research Summary

This project had three research aims, as follows:

1. Quantify and assess the static and dynamic load capacity of ground support systems typically used in deep underground metal mines.
2. Develop methods of controlling fault slip potential to limit the magnitude of mining-induced seismic events and thus reduce the dynamic loads applied to ground support elements.
3. Modify support installation equipment and procedures to protect miners during the installation and rehabilitation of ground support.

Maintaining ground control safety while mining narrow veins in deep underground mines poses major technological challenges. The extreme stresses associated with mining at greater depths—often a mile beneath the surface—can lead to mining-induced seismic events that endanger the workforce and damage ground support, underground entries, and mining equipment.

In cooperation with the mine staff at a collaborating deep vein mine, state-of-the-art technology was applied and innovative measures were developed to significantly improve the ground control safety of underground miners. This overall objective was achieved through completion of the following research tasks:

1.  monitoring fault movement, stress distribution, ground support loading, entry deformation, and seismicity at a collaborating mine to identify fault slip mechanisms and ground control hazards;
2. conducting innovative tests to quantify and improve the performance characteristics of integrated ground support systems, particularly their energy-absorbing properties;
3. developing modeling techniques to analyze the stability of underground entries and the behavior of ground support subjected to dynamic loading; and
4. examining the equipment and procedures that are used to install and rehabilitate ground support.

Research concerning ground support testing and assessment methods and innovative equipment and procedures for installing ground support was continued under the Durable Support for Western U.S. Underground Metal Mines project. Numeric modeling of dynamic loading conditions and the monitoring of mining-induced seismic events, fault movement, stress distribution, ground support loading, and entry deformation will continue at a collaborating underground metal mine as part of the Alternative Mining Methods for Challenging Environments project.