An analysis on the effect of crosscuts within shaft protective pillars on deformations of the surrounding rock mass deformations

The development of crosscuts within mining shafts’ protective pillars causes a change of state of stress in the surrounding rock mass. It also causes deformations of the rock mass and the surface. It is essential to conduct prediction analysis of the deformations and stresses in order to secure a proper functioning of a shaft located within the protective pillar. It is recommended that the analysis should be based on the integration of the finite element method (FEM) and geodetic monitoring results. FEM makes it possible to determine the rock mass stresses and displacements in the shaft protective pillars and in the surrounding rock mass. It makes is possible to determine the safety and proper functioning of the shaft. The results of the FEM analysis of the impact of crosscuts and mining activities on rock mass deformations inside and on the surface of the protective shaft pillar are presented. The influence of mining extractions was investigated. The mining panels were located around the safety pillar in three regions NW, SE and SW and the crosscut were located within the safety pillar. The presented methodology will allow for the determination of the deformations and strains in case of farther development of crosscuts within the protective shaft pilar and by planned mining activities around the pillar.