Development of an integrated geotechnical database and associated analysis tools for excavation design in seismically active underground mines

This paper presents the development and assessment of an integrated geotechnical database for a hard rock, seismically active, underground mine located in the Abitibi-Témiscamingue mining district in Quebec, Canada. The integrated geotechnical database incorporates a geomechanical database with mining planning and seismic analysis. The database was created from the geological and geotechnical information gathered in borehole logs covering the time period of January 2000 to January 2017. The integrated geotechnical database and associated tools allow analysis of rock mass property variation in space and in relation to geological and geomechanical parameters. Two rockmass properties are investigated to illustrate this. The uniaxial compressive strength (UCS) was used to illustrate the applicability of the tools to investigate intact rock properties. The study of the major factors influencing UCS examined the impact of boreholes tested, lithologies, depth, Young’s modulus, and a combination of these categories. Spatial visualization and basic statistical analysis were performed. The rock mass spatial and temporal degradation was also studied in relation to mining activities in the geotechnical model. Rock quality designation (RQD) analysis was conducted as an illustrative example of an investigation on structural rock mass properties. Quantitative and statistical analysis to identify and investigate the major factors influencing RQD examined drilling dip, distance from a development drift, time evolution and distance to a fault. The development and assessment for an integrated geotechnical database provide valuable visual and quantitative information for the design of mining infrastructure in a seismically active underground mine.