Figure 4 – CumHits vs. axial stress σ for BH3-roof The figure 5 presents the cumulative acoustic emission hits (CumHits) versus axial stress σ during uniaxial loading, illustrating a distinct transition from near-silent behaviour to a rapid increase in AE activity, where the Kaiser point (σK) is identified. Figure 5 – CumHits–σ curve showing the identified Kaiser point (σK). Figures 6 and 7 present the estimated in-situ stress levels derived from acoustic emission measurements and Kaiser effect analysis for core samples obtained from boreholes drilled in the roof and sidewalls. 0 20000 40000 60000 80000 100000 120000 0.000 10.000 20.000 30.000 40.000 50.000 60.000 CumHits σ [MPa] Dolomite_0,20 Dolomite_0,45 Dolomite_0,80 Dolomite_0,95 Dolomite_1,65 Dolomite_2.50 Dolomite_3.50 Dolomite_3.75 Dolomite_4.35 0 10000 20000 30000 40000 50000 0.000 5.000 10.000 15.000 20.000 25.000 30.000 35.000 40.000 CumHits σ [MPa] Identified Kaiser point
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