1483 a) b) Figure 10 – Map of axial forces in rock bolts on the 7th day of measurements: (a) chainage 564 m, (b) chainage 936 m On the final day of measurements, a slight increase in tensile axial forces was observed, on the order of 40÷60 kN, while the zones of their highest concentration remained unchanged compared to the initial stage of roadway development. At chainage 564 m, distinct zones of elevated tensile forces were identified, concentrated in close proximity to the roadway roof. The isoline pattern indicates local stress concentrations, typical of areas characterized by a higher degree of rock mass structural disturbance. The force distribution is relatively orderly, suggesting a stabilized load transfer mechanism in this area (Fig. 11). In contrast, at chainage 936 m, the spatial distribution of tensile axial forces is more heterogeneous, with maximum values occurring in zones different from those observed at the 564 m station. This indicates the local nature of stress interactions, controlled by geological structure, the degree of rock mass fracturing, and the mining history of the area. Despite these differences, the observed force magnitudes remain at a comparable level, indicating the absence of significant stress anomalies in the rock mass. a) b) Figure 11 – Map of axial forces in rock bolts on the 385th (final) day of measurements: (a) chainage 564 m, (b) chainage 936 m The results obtained from monitoring of roof rock separations, loads in instrumented rock bolts, and the extent of the fractured zone clearly indicated the need to reinforce the roadway roof with additional rock support elements. In the section between chainages 245 m and 287 m, an intensification of destructive processes in the roof was recorded, manifested by an increase in separation values to approximately 56 mm. This level exceeded the second alarm threshold adopted in the roadway stability
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