The research described in this thesis was concentrated on two main subjects:​ the evaluation of steel rock supports as waveguides for transmitting high frequency emissions and the analysis of Acoustic Emission (AE) data collected in laboratory and field environments.

The results of laboratory tests illustrate that the amplitudes of AE events are not influenced by the angle at which the events enter the surface of steel waveguides. In contrast, the direct attachment of a transducer to the rock produces a directional response of AE events and the event amplitudes depend on the angle at which they enter the transducer's piezoelectric plate. The uniform characteristics of AE events captured by the transducer attached to the end of a steel rockbolt causes the quality of AE data captured by this configuration to be greatly improved over the quality of AE recorded by the direct transducer attachment to the rock surface.

Further laboratory experiments indicated that steel with a high carbon inclusion content subjected to high tension did not produce any AE till reaching the yield point. Most of the rockbolts used in the underground mines are made from such steel;​ therefore the yield point of steel with a high carbon inclusion aligns with the first rise of AE. The ability to recognize the moment when the steel support begins to yield is an additional benefit of AE monitors using transducer-rockbolt attachment because it can warn the mining personnel of high stress applied to the rock support.

The pullout tests with fully grouted rockbolts showed that the event rate of the AE generated by failing grout was very low and would not alter the interpretation of the AE data collected through rockbolt attachment.

The attenuation of the AE events traveling through steel rockbolts was established using a high frequency waveform generator. The results of these experiments provided valuable data about the attenuation factor for AE events traveling through different lengths of steel bar.

Field data collected at Kidd Creek, Creighton and Williams Mines indicated that the high frequency monitors can be successfully used for monitoring of the stress changes in the local rockmass.

The greater sensitivity of high frequency monitors over the low frequency mine wide systems was illustrated by comparing the quantity of microseismic events collected by both systems from the same monitoring areas. Similar comparison studies were also used to determine the range at which the local stress changes in the rockmass could be detected by monitoring the high frequency events.

Postproduction blast monitoring of the rockmass illustrated that AE monitoring can be used to determine if the level of AE after extraction of the mine stopes returned to the preblast conditions and therefore, to determine the stability of the monitored ground.