Investigation of relationship between drillability with some engineering properties of rocks in tunnel location of cambasi regulator and HES

Drillability may be defined as the penetration rate of the bit within the formation (as m/min, cm/min or mm/min). The number of factors that affect penetration rate are numerous. During determination of drillability, the values that are measured for different formations should be comparable with each other; the penetration rate should be measured by using the same equipment and under similar conditions. The drilling process is a complex phenomenon that is affected by several factors. Bit type and bit diameter, bit rotation, torque and circulation fluid are the parameters that are controllable. On the other hand such uncontrollable parameters including the physical and mechanical properties of the rock, geological conditions and abrasive mineral proportion are also effective during drillability of rocks.The determination of uncontrollable properties during rock drillability (rock properties), makes it possible to select the controllable parameters such as the drilling method that shall be used during drilling, bit type, bid rotation, bit load, drill string properties, pump type, drilling fluid/air velocity and volume, personnel optimally during their project preparation stage. The prediction of drilling rates may be used for the calculation of financial portraits and the planning of the duration of drilling work.In this thesis, penetration rate was studied by considering the effects of both operational drill parameters, e.g. thrust, thrust and strength properties of drilled rocks, e.g. uniaxial compressive strength in 4 core drilling which was drilled for tunnel geotechnical investigation. Based on the data derived from the field and laboratory studies, the relationships between the above mentioned parameters were investigated to obtain optimum penetration rates for drilled rocks.Finally, optimum thrust, rotation and penetration rates were established for drilled rocks by analysing the relationships between penetration rates and some rock properties.