Influence of excavation thickness on the stress distribution around the barrier pillar Rizto Salia Zakri (a,b*), Ridho Kresna Wattimena (a), Simon Heru Prassetyo (a), Tri Karian (a)
a)Mining Engineering Study Program, Faculty of Mining and Petrolium Engineering, Institut Teknologi Bandung, 40132, Bandung, West Java, Indonesia
*riztoszakri[at]gmail.com
b)Mining Engineering Departement, Faculty of Engineering, Universitas Negeri Padang, 25131, Padang, West Sumatera, Indonesia
Abstract
Underground coal mining using the longwall method is one of the methods that has the best recovery. Obtaining good recovery will affect the dimensions of the excavation which will have an impact on underground stability. The thickness of the coal seam plays a role in determining the height of the excavation which theoretically will have an impact on the height of the GOAF that will be formed. The thickness of the excavation will influence the stress distribution that will occur during and after the excavation takes place. Based on two-dimensional numerical modeling using longitudinal sections, it can be seen that the thickness of the excavation has an effect on the stress distribution on the barrier pillar, the thinner the coal is mined, the greater the stress that occurs on the barrier pillar, conversely, the thicker the material that is mined, the smaller the stress that occurs on the barrier pillar. , these results were obtained by modeling with the assumption that the height of the goaf due to excavation was 4x the height of the excavation. Meanwhile, the depth of excavation does not have a significant influence on stress changes in the barrier pillar.
