Study of correlation between specific energy of cutting and physical properties of rock and prediction of excavation rate for lignite mines in Cayirhan area, Turkey

Laboratory specific energy (SE) is a reliable indicator to evaluate the rock cuttability and efficiency for mechanical excavation in mining and tunneling applications. In this study, various geological units encountered in lignite mines were studied through laboratory tests and measurement of specific energies in nine different rock types and two different lignite samples from Cayirhan area, Ankara, Turkey. The correlation between the physical and mechanical properties of various rock including uniaxial compressive strength, tensile strength, cone indenter hardness, shore hardness, Schmidt hammer hardness, and density with measured SE of cutting were also investigated. A prediction model for SE based on statistical analyses using regression technique of laboratory test results are also introduced. The model can be used for estimating the SE from the rock physical and mechanical properties, and in turn offer an estimate of machine performance for pertinent mechanical excavators such as roadheaders, continuous miners, and drum shearers.