An interpretation model for measurement while drilling in large open pit mines

摘要

The critical and most difficult element of Measurement While Drilling is to determine the effect on blasting activity of a particular relationship between drilling parameters and rock mass property. This relationship is called interpretation model. Described in this paper is an interpretation model based on the law of mechanics. Experiments were performed to validate this model. A parameter, named specific energy of rock for drilling, was derived. Field study showed that this parameter is a dominant variable. Rocks drilled at Aitik mine in Sweden produced wide variations in specific energy levels. A comparison of data demonstrated that the specific energy has a good correlation with rock types. The specific energy also has a good correlation with drilling performance: the higher the specific energy, the lower are the penetration rate, the motor current and the rotation speed.