Guidelines for stabilizing historic mine workings

摘要

Historic mine workings are present throughout several regions of the United States. The presence of these workings can pose a significant challenge to engineering projects requiring competent foundation conditions, such as roads, buildings, dams, etc. Mine workings such as shafts, open stopes, drainage tunnels, and drifts may leave unstable voids in the subsurface that may become public safety hazards, compromise foundation stability, and adversely impact engineered structures.rnIn order to stabilize historic mine workings, geotechnical investigations and engineering analyses are required to assess site conditions and the associated risk to nearby or proposed structures. The design of a suitable stabilization approach to historic mine workings needs to consider many facets of rock and soil mechanics, including:rn1. Existing and induced stress state within the region of the mined workings;rn2. Rock mass quality;rn3. Crown pillar stability;rn4. Cavability of the surrounding rock mass; andrn5. Settlement of backfilled materials.rnThis paper presents practical guidelines for the stabilization of historic mine workings. The paper also discusses important implementation and constructability issues which can affect the success of the project.