Prediction of Reaming Performance of Vertical Raises Using Rock Properties and Operational Parameters

Raise Boring Machines (RBMs) as the fast and safe operation of drilling excavation of vertical and/or inclined shafts are used in the mining and construction projects for different purposes. Proper selection and accurate performance prediction of these machines are very important issues affecting the cost estimation and planning of the projects. However, reliable models for predicting performance of these machines have been quite limited. This study aims to develop empirical performance prediction models for vertical reaming operations (unit penetration rate and specific energy parameters) by using physical-mechanical properties of rock samples, operational parameters of pilot hole drilling and reaming. Field performance data of the pilot hole drilling and reaming operations, as well as rock samples, are collected in different raise excavation projects in Turkey. The evaluation indicates that weight on bit of pilot hole drilling with the rotational speed of reaming and static elasticity modulus of the rocks could be used to predict the field specific energy. Consumed reamerhead torque and indirect tensile strength and dynamic elasticity modulus of rocks could be used to predict the unit penetration rate.