231 This paper presents a comprehensive analysis of the stability of a roadway maintained exclusively with a self-supporting rock bolt system, constructed at great depth under conditions of complex geological structure and strong mining-induced influences, based on a case study from the “Budryk” hard coal mine in Poland. The presented investigations represent one of the few case studies of this type involving a roadway driven with a self-supporting rock bolt system at a depth of approximately 900 m, constituting a significant contribution to the advancement of knowledge on the application of such support systems under difficult geological and mining conditions. The study combines detailed laboratory and in-mine analyses of rock strength parameters with an extensive in situ monitoring program, including measurements of fractured zone extent, roof rock separations, roadway convergence, and loads and stress levels in rock bolts. This broad scope of observations enabled a multi-faceted assessment of the interaction between the rock bolt support system and the surrounding rock mass, as well as identification of mechanisms responsible for local deterioration of stability conditions. The results clearly confirmed that the effectiveness of a self-supporting rock bolt system is strongly dependent on local geological and mining conditions. Of particular importance are the quality and stratification of roof rocks, the presence of coal layers in the immediate roof, the degree of rock mass fracturing, and the orientation of the roadway relative to the direction of maximum horizontal stresses. It was demonstrated that unfavourable roadway orientation with respect to the principal horizontal stress component leads to asymmetric development of roof deformations and local stress concentrations, which is directly reflected in the distribution of roof separations and bolt loads. The analyses conducted demonstrated that continuous monitoring of rock mass behaviour and flexible adjustment of the bolting scheme to current conditions are key elements for the safe maintenance of roadways supported by self-supporting rock bolt systems. The application of additional cable bolts in zones characterized by increased fractured zone extent and exceedance of alarm thresholds effectively limited further deformation development and restored the stability of the support–rock mass system. The results presented confirm that, with proper identification of geomechanical conditions, appropriate selection of support parameters, and active response to monitoring outcomes, it is possible to safely and effectively maintain roadways supported solely by rock bolt systems even under difficult and variable geological conditions. The experience gained provides a solid basis for further optimization of design principles for self-supporting rock bolt systems and for their wider application in Polish hard coal mines. Reference [1] Barczyk J., Kowalski S., Lampert G., Dubiel G., Głuch P. (2001): Rozwiązania obudów kotwiowych zastosowane w kopalniach Rybnickiej Spółki Węglowej. Nowoczesne
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