ABSTRACT
This paper describes results of research at the Spokane Research Laboratory (SRL) of the National Institute for Occupational Safety and Health (NIOSH) to assess hazards and improve design criteria for ore passes in underground mines. Analysis of Mine Safety and Health Administration (MSHA) accident statistics has identified ore pass hazards as a significant safety problem in U.S. underground metal mines. Dynamic loads induced by large, falling masses of ore or waste rock and removal of blockages by blasting can cause structural or functional failures in control gates and chutes. Existing design standards for ore passes are essentially rules of thumb based on simplified equilibrium analyses, model experiments, empirical observations, and experience. The overall goal of this project is to prevent injuries and fatalities through assessments of ore pass hazards, experimental and computer analyses of current designs, and laboratory and field measurements of loads and structural responses in ore passes.
