223 The roadway had a width of 5.6 m and a height of 3.4 m. The primary rock bolting system consisted of steel rebar bolts with a total length of 2.5 m, a diameter of 22 mm, and a minimum load-bearing capacity of 260 kN (Fig. 2). The bolts were installed using resin cartridges with a total anchorage length of 1.250 mm. Boreholes were drilled using a handheld drill with a diameter of 28 mm, allowing at least 90% of the borehole volume to be filled with resin. Roof support was supplemented with steel mesh with a 100 × 100 mm aperture, reinforced at overlaps with an additional steel bar. In the basic configuration, six rebar bolts were installed in the roof, while three bolts were installed in each sidewall, with a spacing of 0.8 m. Figure 2 – Rock bolt support scheme in the roadway A monitoring system based on the observation of rock layer separation was implemented in the roadway using three-level extensometers installed in the roof at the left sidewall, along the roadway axis. and at the right sidewall (Fig. 3). In addition, investigations using an endoscopic camera were carried out, enabling the observation of roof rock damage propagation. A key component of the monitoring system was the recording of rock bolt loads, which reflected the stress state of the bolts in response to roof deformation (Fig. 4). The adopted measurement system, together with defined safety thresholds, enabled continuous assessment of roadway stability, analysis of the interaction between the support system and the rock mass, and the implementation of preventive measures. It was assumed that
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