Unrelieved Spesific Energy Estimation from PLCM and FLCM Linear Rock Cutting Tests and Comparison with Rock Properties
Estimation of laboratory specific energy values from mechanical rock properties to predict the efficiency of mechanical miners (tunnel boring machines, roadheaders, continuous miners, shearers, etc.) is the basic aim of this study using laboratory linear rock cutting devices. Specific energy is defined as the amount of energy required to break a unit volume or weight of rock expressed in kWh/m3 or MJ/m3. This value can be obtained from full-scaled laboratory linear (FLCM) or portable linear rock cutting (PLCM) experiments at different cut spacings and depths, respectively. For this purpose, full-scaled linear and portable linear rock cutting experiments are performed on 5 different blocks of rock samples including Beige marble, Kufeki limestone, Travertine, Sandstone and Limestone. Cutter forces acting on a cutter in three orthogonal directions (cutting force, normal force, and sideway force) and, specific energy values are measured during testing. In addition, some physical and mechanical property testing are carried out and the relationships between optimum specific energy values and rock mechanical properties are analysed using regression analysis. Statistical analyses suggest that the unrelieved specific energy values can be predicted reliably from rock mechanical properties to select the most efficient mechanical miners for a given rock or mineral. Specific energy, Mechanical Excavation, Linear rock cutting.