A Numerical Modelling Approach to Find the Stability of RIB and Snook in Mechanised Depillaring Panel — A Case Study of Kurja Mine

Abstract

Depillaring by conventional techniques created many irregular shaped pillars, mainly located at shallow depths in different coalfields of India. Continuous Miner Technology (CMT) has been introduced to extract these coal pillars scientifically with safety and productivity with greater depth. Leaving a proper sized rib or snook is a legal requirement as it decides the efficiency and safety of the pillar. However, CMT of square/rectangular shaped pillars created irregular shaped rib and snook. With the conventional empirical formula it is difficult to estimate the strength of such ribs or snooks. These ribs or snooks should be of sufficient size to protect the adjacent slicing operation and junction as well as they should fail in a controlled manner when machines shift inside the extraction. Field studies of different mines found several factors affecting the design of rib or snook. They are various types of induced stress, geological disturbances, manner of extraction etc. Proper assessment of the performance of different sizes and shapes of ribs and snooks in the field is complex due to the problematic underground mining environment for depillaring. For successful operation of the CMT required to study every depending parameter scientifically. Therefore, a numerical model is conducted to estimate the factor of safety of rib and snook to calculate the rib and snook stability. Results of field and simulation studies are presented and discussed in this paper to determine the rib’s stability in the continuous miner panel to create a safe environment for the men and machines.