Determination of the most effective longwall equipment combination in longwall top coal caving (LTCC) method by simulation modelling

Simulation modelling turned out to be very suitable for this study since there is no chance to test alternative production methods during the ongoing work of the mine. It would be very costly to set up a pilot face to test alternatives, also. By the use of simulation, it is possible to test the effects of new methods and factors economically and quickly. Imitating the operations of real-life systems or processes is the main purpose of computer simulation. Operational scenarios can be tested and evaluated without the need or expense of physical experimentation. Applications have been developed to simulate the space and time relationships between mining equipment, mainly in connection with transport systems [8-10]. Tsiflakos and Owen [11] discussed the philosophy, methodology, objectives, mining process logic, program structure and its state-of-the-art for a recently developed mine simulation model. By Connor et al. [12], a two-dimensional rigid block computer model was used to simulate discontinuities within the strata overlying a longwall coal mine. Hunt [13] simulated the ore haulage in Henderson molybdenum mine. The purpose of the simulation was to demonstrate to mine management how simulation could be used to assist in optimizing ore transport using existing trains, trucks, and ore passes. Today, there exist specially designed high-level simulation programs. The most commonly used simulation languages are GPSS (General Purpose Simulation System), GPSS/H (event-driven version of GPSS) and ARENA. Also, Vagenas [14] and Sturgul [15,16] have applied discrete event simulation to both underground and open-pit mining operations using GPSS and GPSS/H. SIMAN was used by Tan and Ramani [17] to study belt networks. Kolonja [18] used SIMAN for studying the various dispatch criteria for open pit mines. Many of the mine simulations done using ARENA were proprietary in nature and did not appear in the literature. In addition to these studies, web-based simulation programs have also been made presenting a newly developed, user-friendly visual simulation computer tool which helps mine operators to plan the optimum mining sequence for different mine geometries and equipment layouts [19]. Another study contributes to the body of knowledge by developing a robotization and stability control (RASC) model for operating dump trucks [20]. Konyukh and Ramazanov [21] aimed in their study the optimal use of LHD vehicles working in underground by an operator at surface using the GPSS/H simulation language. When searching the studies carried out up to now, it can be seen that especially haulage equipment have been simulated at the underground mining methods room-and-pillar and sublevel caving so far, and, longwall mining has not widely been subject to simulation. © 2006 Elsevier Ltd. All rights reserved.