227 a) b) c) Figure 8 - Roof separation values at chainage 936 m: (a) left sidewall, (b) roadway centreline, (c) right sidewall 4.3. Convergence The roadway section between chainages 230 m and 1,040 m included eight stations for convergence measurements, located between approximately 414 m and 1,063 m along the roadway length. Figure 9 presents the maximum values of vertical and horizontal convergence recorded during the development stage as a function of roadway chainage. The highest values of vertical convergence were recorded in the vicinity of chainage 563 m, where the reduction in roadway height reached approximately 29 cm. This location represents a clearly dominant point along the analysed section and indicates locally unfavourable geomechanical conditions. Significant vertical convergence was also observed at chainages 503 m (approximately 19 cm) and 655 m (approximately 13 cm). At these locations, the increase in convergence occurred gradually throughout the entire excavation stage, suggesting long-term stress influence and progressive rock mass deformation. At the remaining measurement stations, vertical convergence was markedly lower and ranged from approximately 3 to 11 cm, which can be considered relatively small values from
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