Shahrood University of Technology Journal of Mining and Environment 2251-8592 8 3 2017 07 01 Determination of a suitable extraction equipment in mechanized longwall mining in steeply inclined coal seams using fuzzy analytical hierarchy method (Case study: Hamkar coal mine, Iran) 487 499 847 10.22044/jme.2017.847 EN A. Hosseini University of Applied Science Technology, Kerman, Iran M. Najafi Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran Seyed A. Shojaatlhosseini Department of Mining Engineering, Higher Education Complex of Zarand, Zarand, Iran R. Rafiee School of Mining, Petroleum & Geophysics Engineering, Shahrood University of Technology, Shahrood, Iran Journal Article 2016 11 20 The longwall mining method is one of the most applied methods in extracting low-inclined to high-inclined coal seams. Selection of the most suitable extraction equipment is very important in the economical, safety, and productivity aspects of mining operations. There are a lot of parameters affecting the selection of an extraction equipment in mechanized longwall mining in steeply inclined coal seams. The important criteria involved are the geometric properties of coal seam (dip, thickness, and uniformity of coal seam), geological and hydraulic conditions (faults, fractures, joints, and underground water), and geomechanical properties of coal seam and surrounding rocks. Extraction of inclined coal seams with gradients greater than 40 degree is different from low-inclined seams, and requires a special equipment. Therefore, the influence of the above-mentioned parameters must be considered simultaneously in the selection of extraction equipment for steeply inclined seams. This paper presents an application of the Fuzzy Analytical Hierarchy Process (FAHP) method in order to select a suitable extraction equipment in the Hamkar coal mine. In the proposed FAHP model, fifteen main criteria are considered, as follow: dip of coal seam, thickness of coal seam, seam uniformity, expansion of coal seam, faults, fractures and joints, underground waters, hangingwall strength, footwall strength, coal strength, <em>in-situ</em> stress, equipment salvage, dilution, system flexibility, and operational costs. Among the 6 considered longwall extraction equipment system alternatives, the findings show that the most suitable extraction equipment system is shearer on footwall and a support system using hydraulic props and the transport of coal with the force of gravity. https://jme.shahroodut.ac.ir/article_847_780be321efae7a9f7d9b3f8563064605.pdf