Drilling and blasting designs for parallel hole cut and V-cut method in excavation of underground coal mine galleries

Abstract

The Karadon mine, where field studies were carried out, is located in the north west of Turkey and is considered to be a highly gaseous coal mine. Explosives and ignition systems used in underground coal mines are determined by laws, statutes, regulations and strict rules. Restrictions arising from legal requirements, such as restrictions on charging and stemming lengths and blasting agents to be used, make the use of well-known tunnel blasting techniques difficult or sometimes not possible. In such cases, the designs made with the equations given in the literature must be revised and rearranged. The objective of this study is to recommend solutions to the blasting difficulties that are encountered in gaseous underground coal mines in which there are limitations arising from legal requirements. This study summarizes and analyses the blasting practices currently employed at Karadon mine along with their disadvantages. New blasting designs were then made using the methods suggested in the literature, and these designs were revised according to legal requirements. By keeping the charge concentration constant relative to its original value, the burden and spacing distances were adjusted. As a result of this study, it has been seen that rearrangement by keeping the charge concentration constant compared to its original value is an appropriate engineering solution.

Comparison of Tunnel Construction Cycle with NTNU Model for the Headrace Tunnel of Seti Khola Hydropower Project

“…The criteria for the selection of cut is vested in parameters such as the size of the tunnel, diameter of drill holes, preferred advance rate, and use of equipment besides the character of rock and rock mass [2]. The proper blast design should be used [3].…”