Optimisation of rock mass quality parameters for the initial geotechnical investigation of a vertical shaft: Gosowong Gold Mine Project Case Study - North Halmahera
Keywords:Rockmass, vertical Shaft, Geotechnical underground
This article presents a case study that highlights the importance of a thorough geotechnical assessment at an early stage of project development. Shaft ventilation is one of the critical elements in underground mines, providing oxygen and ensuring air quality for breathing, removing noxious gases from equipment and explosions, reducing the natural temperature of the rock, and more, so stability analysis is required for design and strategy prior to shaft opening. Through extensive field surveys, drilling and laboratory testing, the project team has gathered data to assess rock quality parameters, including rock strength, geological structure and hydrogeological characteristics. The McCracken and Stacey (MS) method is one such empirical approach to assist shaft development risk assessment. The results of this analysis allowed the identification of potentially unstable zones. It was concluded that 45% of the planned ventilation shafts have stability problems due to rock mass variations. The risk value of the shaft development plan was obtained with a high failure risk of 25%, a medium failure risk of 33% and a low failure risk of 42% based on the raise bore quality index (QR).
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This is an open access article under the CC BY-NC-ND license Creative Commons Attribution-Noncommercial 4.0 International (CC BY-NC 4.0).