TY - JOUR N2 - This article describes stability issues of main excavations in deep copper mines in Poland, from the perspective of mining work safety. To protect main transportation and ventilation routes, parts of rock are left untaken to form so-called protective pillars. The problem was to determine the size of main excavations protective pillars in deep underground copper mines in which provide stability of main excavations. The results of numerical simulations of the stability of protective pillars under specific geological and mining conditions are presented, covering: underground depth and width of protective pillar, number, size and layout geometry of protected excavations, as well as the impact of parameters of surrounding gob areas. Problem was solved applying numerical simulations based on the finite element method which were performed in a plane state of strain by means of Phase2 v. 8.0 software. The behavior of the rock mass under load was described by an elastic-plastic model. The Mohr-Coulomb criterion was used to assess the stability of the rock mass. The results of numerical modeling have practical applications in the designing of protective pillars primarily in determining their width. These results were used to prepare new guidelines for protective pillars in Polish copper mines in the Legnica-Glogow Copper District. L1 - http://www.czasopisma.pan.pl/Content/109029/PDF/Archiwum-63-4-10-Pawelus.pdf L2 - http://www.czasopisma.pan.pl/Content/109029 PY - 2018 IS - No 4 EP - 946 DO - 10.24425/ams.2018.124985 KW - protective pillars KW - main excavations stability KW - deep underground copper mines KW - numerical modeling A1 - Adach-Pawelus, Karolina A1 - Butra, Jan A1 - Pawelus, Daniel PB - Committee of Mining PAS VL - vol. 63 DA - 2018.12.17 T1 - The Issue of Determining the Size of Main Excavations Protective Pillars in Deep Underground Copper Mines SP - 935 UR - http://www.czasopisma.pan.pl/dlibra/publication/edition/109029 T2 - Archives of Mining Sciences ER -