226 Along the roadway axis (Figs. 7b and 8b) and at the right sidewall (Figs. 7c and 8c), separation values were generally lower and more uniform over time. This may indicate more favourable geomechanical conditions and a more even stress distribution in these zones. In particular, at the 936 m station, a clear stabilization of separations was observed following the initial period of rapid changes, suggesting effective performance of the applied support system. The obtained results clearly confirm the key role of the shallow anchorage zone in maintaining roadway roof stability and demonstrate significant variability of deformation depending on the location within the roadway cross-section. The use of extensometers installed at three points across the cross-section enabled a comprehensive assessment of roof behaviour and identification of zones most susceptible to deformation development. a) b) c) Figure 7 - Roof separation values at chainage 564 m: (a) left sidewall, (b) roadway centreline, (c) right sidewall
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