ABSTRACT
Longwall mining is now predominant especially where deep coal mining is practiced. It is a requirement of the method that long faces are equipped with exceedingly expensive machinery. The high capital cost of such faces necessitates high volumes of output and hence high rates of advance. Any attempt to increase the rate of advance is constrained by ground control considerations. The precise way in which these constraints are imposed is analysed and appropriate models developed. A mathematical model that relates ground control criteria to the rates of face advance is introduced. The model is used to determine the most economical rate of advance with respect to roof stability in different parts of the longwall panel. The results of this research can serve as useful tools in designing future highly mechanised longwall faces.
