Jinsheng Chen

Date of Graduation


Document Type



For the purposes of production and safety, the roof exposed in the working area of a longwall face must be supported and protected. A hydraulic powered support with an improper structural design or insufficient capacity may result in roof failure or falls at the face, or its structural failure under intensive roof activity, while a heavier-than-required support can dramatically increase its cost. To ensure a safe and stable face condition at a minimum cost during the longwall retreat, the roof loading behavior above the face support, the structural stability and resultant loads of a hydraulic powered support under different mining conditions must be fully understood. In this dissertation, the author has developed a comprehensive program of designing hydraulic powered supports for longwall mining based upon roof activity monitoring and analysis, longwall roof classification, analysis of support resultant loads and floor pressure distribution, analysis of support resistance vs. roof load demand. By using the theories of cantilever beam and artificial neural networks, and field monitoring data of support leg pressure, the relationship between support performance parameters and parameters related to mining and roof conditions has been derived and can be used with confidence for both evaluation of the powered supports in service and design of new powered supports once roof and mining conditions are known.