Abstract
Since the early 1980s, the longwall method has developed into the safest, highest producing and most productive form of underground coal mining, rivalling the performance of many surface mining operations. This is due in large part to the rapid uptake of computer based technologies for automation and monitoring; improved reliability and performance of longwall mining equipment; and the adoption of plant management and loss control principles. This situation has many important implications for the geoscience and geotechnical engineering professions. For example, lost opportunity costs associated with loss of ground control are now so high that many of the simple observational and empirical approaches traditionally applied to geotechnical designs and operational aspects in longwall mining are no longer commensurate with the business risks that have to be managed. There is an increased need for geotechnical input to be based on sound engineering principles that encapsulate measured ground behaviour, applied mechanics, and numerical modelling. Ongoing research is important to support this need.
This chapter addresses geotechnical principles and practices relevant to satisfying these engineering requirements, making extensive use of figures and photographs to illustrate important concepts. It considers panel layout options and associated chain pillar design; traces the history of powered support design to draw learnings about their static and kinematic requirements; identifies and assesses operational variables, including cutting and support techniques, powered support maintenance, and face operational practices. It then reviews face behaviour and ground control requirements and practices; and evaluates the design and support of installation roadways and longwall recovery roadways, including pre-driven roadways.
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Galvin, J.M. (2016). Longwall Mining. In: Ground Engineering - Principles and Practices for Underground Coal Mining . Springer, Cham. https://doi.org/10.1007/978-3-319-25005-2_9
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