Mine drift diagnosis using wave response

Abstract

A sonic/ultrasonic wave response method, as part of an integral roof diagnosis technique is analyzed. The purpose of the test is to assist in the risk assessment of the stability of an existing excavation. The main objectives of the research effort are to improve detection, discrimination, and decision-making using wave response. A number of sonic/ultrasonic tests were conducted both in the laboratory and in the field. A high-energy ultrasonic transducer as well as an impact device were used to resonate rock slabs. The fracture depths of rock slabs were found to be inversely related to the resonance frequencies measured. The agreement between identified and actual fracture depths was acceptable. Field tests also showed that small loose rock -volumes or layers can be clearly distinguished from solid formations by analyzing their wave responses. In conclusion, the wave response technique has a potential for being used in the diagnosis of roof stability.