Raise Boring Machine performance in the Yusufeli Dam and HEPP Project
Performance of a Raise Boring Machine (RBM) used in Yusufeli HEPP project in Turkey is evaluated in this study. The depth and diameter of the energy shaft are 130 m and 2.44 m, respectively. The drill core samples were obtained from the site (diabase and granodiorite) and compressive strength, tensile strength, static elasticity modulus and Poisson’s ratio, dynamic elasticity modulus and Poisson’s ratio tests were applied on them. The RBM performance parameters such as pulling force, reamerhead torque, penetration rate, and stoppages were recorded in the field. The relationships between the rock brittleness index and the field performance parameters were investigated based on a previous empirical model. The investigation indicated that the rock brittleness index seemed to be a reliable predictor for estimation of the torque and pulling force, while it could not predict reliably the penetration and specific energy.