200 front and the mined-out area. These devices consist of two coaxial sleeves of different diameters, where one sleeve moves inside the other; a millimetre scale enables direct reading of closure. A known limitation of this approach is the relatively low reading frequency and limited sensitivity to short-term deformation increments. Figure 5 - Location of convergometers within the analysed mining panel (left) and results of convergence measurements in the analysed panel (right) For comparison with numerical outputs, convergence in the model was defined as the sum of roof deflection magnitude and floor heave: = ห ห− (1) where is total roof displacement taken as an absolute value due to the sign convention (negative roof displacement in the model). 2.4. Calibration Calibration was performed iteratively by adjusting rock mass strength parameters within the GHB/GSI framework to achieve agreement between simulated and measured convergence trends across the monitoring network. The calibration window covered two consecutive months of observations, allowing the fitting to reflect both spatial variability and the deformation response associated with mining progress. To reproduce the observed contrast between higher deformation in the active mining zone and lower deformation in long-life excavations, the model was subdivided into four geomechanical zones with separate parameter sets (Figure 6). This zoning approach allowed spatial differentiation of rock mass quality and disturbance (GSI and D), improving consistency between simulations and field observations.
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