Performance of Raise Boring Machine (RBM) in Low to Moderately Hard Hornfels Rocks: A case Study of Efemcukuru Gold Mine in Turkey
Raise Boring Machine (RBM) provides a safe means of excavating a circular hole between two levels without the use of explosives. These machines were developed for the underground mining industry but nowadays is increasingly used on infrastructural projects. This paper aimed to assessment of the performance of a RBM during drilling / excavation of a ventilation shaft in the Efemcukuru Gold Mine, Turkey. The depth and diameter of this shaft were 50.60 m and 2.44 m, respectively. The drilled core samples were obtained from the site to define some important physical-mechanical properties. The RBM operational-performance parameters such as daily advance rate, consumed reamerhead torque, net pulling / pushing force and etc. were recorded / calculated in pilot drilling and reaming operations. This investigation indicated that there was a moderate relationship between Brazilian tensile strength and consumed reamerhead torque in moderately hard hornfels rocks.