Evaluation of the risk to underground mine personnel due to the rockmass response to continuous mining operations.

Abstract

The objective of the study was to determine whether there is a difference in the seismic response of the rockmass between 11-day mining cycle and full calendar operations - FULCO. A literature survey was useful to gain insight in the time dependent rockmass response to mining. This helps to understand how the time of day distribution of seismic events can be affected by changes in mining operations. The literature survey did not contribute to the development of particular procedures for the difference in seismic hazard or risk between 11-day fortnight operations and FULCO. Authors developed the simplistic concept of Seismic Exposure (SE). Authors define the hourly hazard as the average number of events greater than magnitude 1. The liability is the average number of workers underground during that hour. The average daily risk (daily SE) is the product of the hazard and the liability. The full risk for the period under consideration would then be the daily SE multiplied with the number of working days. This can be normalized by production for comparison purposes.