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Mining operations disrupt the structure of rock layers, leading to surface deformations and potential mining damage. This issue has been extensively studied since the 19th century using various analytical, geometric-integral, and stochastic methods. Since the 1990s, numerical methods have been increasingly applied to determine changes in the stress and strain states of rock masses due to mining activities. These methods account for numerous additional factors influencing surface deformation, offering significant advantages over classical approaches. However, modelling rock masses presents challenges, particularly in calibrating the mechanical parameters of rock layers, an area extensively researched with numerous publications. In this study, we determined the mechanical parameter values of rock layers at the advancing mining front using a custom Python script and Finite Element Method (FEM) numerical models. We also introduced a modification to evaluate the error of the estimated parameter values. Numerical analyses were conducted for the Piast–Ziemowit mine region in Poland, utilizing mining, geological, and surveying data. Our results demonstrate that accurate calibration of mechanical parameters is crucial for reliable predictions of surface deformations. The proposed methodology enhances the precision of numerical models, providing a more robust framework for assessing the impact of mining activities on rock layers. [ABSTRACT FROM AUTHOR]

The article presents a methodology for determining the value of the expansion coefficient of a reconsolidated caving zone in the context of forecasting the rise in underground mine water levels and consequent surface subsidence caused by the process of flooding the closed coal mines. The paper also provides a brief characterisation of analytical predictive models regarding surface subsidence during the process of flooding coal mines. In order to describe the vertical deformation of the reconsolidated porous rock mass in the caving zone, a linear-elastic medium of Biot was utilised. The conducted theoretical calculations demonstrate a high agreement with the results obtained through the identification of the expansion coefficient parameter based on the analysis of in-situ subsidence measurements in Dutch and German mining areas. The proposed methodology was applied to a real case study involving the forecasting of the impact of the flooding process on the underground workings of the German Ibbenbüren mine. The article constitutes a significant contribution to the field of forecasting the rise in underground mine water levels and surface subsidence during the process of flooding closed coal mines. The presented methodology and obtained results can be valuable for researchers, engineers, and decision-makers involved in the planning and management of mining areas. [ABSTRACT FROM AUTHOR]

The mining areas of the copper ore mines in Poland contain tailings storage facilities. Because of operational safety issues and to minimize the exposure of local neighbourhoods to the risk of such reservoirs failing, mining operations are limited during the period of waste storage, thereby reducing the impact of exploitation on these objects. Nevertheless, continuous monitoring and analysis of the deformation state of reservoirs and associated facilities are required. Monitoring is most often carried out using geodetic methods, while the deformation analysis is based on determining the displacements of control points and making short- and long-term forecasts of changes in land surface deformation. Presented here is an analysis of changes in the state of displacements and dyke deformations of a currently closed copper flotation tailings reservoir that was used in the 1970s. After the storage of waste was stopped, an intensive two-stage mining operation was carried out under the reservoir. The results obtained from the geodetic monitoring of displacements and deformations of the reservoir dyke are compared with the model values, and the usefulness of the applied theoretical model for describing the vertical and horizontal displacements and horizontal deformations is verified. Based on the comparison results, a hypothesis is presented regarding the causes of the actual condition of the movements of the reservoir dam crest against the background of the expected movements obtained from theoretical modelling. The presented conclusions revise a very rigorous approach to protecting flotation tailings reservoirs against the effects of underground mining. [ABSTRACT FROM AUTHOR]

Two commonly utilized methods for propagating uncertainties in model parameters of surface deformation caused by underground mining are compared in this study. These methods enable estimation of standard uncertainties in indicators of surface deformation, specifically: subsidence, tilt, and horizontal strain, to be calculated. The first method is the law of propagation of uncertainty (LPU), based on a first-order Taylor series expansion without the use of higherorder derivatives. The second method is the Monte Carlo (MC) method. It relies on the calculation of many values of deformation indicator for random values of model parameters. It is noteworthy that in the previous research in this field no comparison of these methods was carried out. The calculations performed in this study based on both methods allow the verification of results and the features of both approaches to be compared. Calculations were performed applying the Knothe model, which assumes a normal distribution for the influence function. Both average values and model parameter uncertainties derived from hard coal mining across the entire Upper Silesian Coal Basin (USCB) region of Poland were used in this study. Model parameter uncertainties are high in this case, which is unfavorable for LPU, but results do indicate that this approach can be useful for propagating model parameter uncertainties for the surface deformation caused by underground mining. [ABSTRACT FROM AUTHOR]

Predicting surface deformations caused by underground mining is an issue of significance both for the safety of overlaying facilities and for economic purposes. There are many different models for predicting the impact of underground mining on the land surface. One of them is the Knothe model commonly used in Poland and in the world. The paper presents two methods of estimating Knothe model parameters uncertainty. The parallel application of two methods enables the mutual verification of the results obtained and the identification of the potential errors and their sources in the case of any discrepancies. The first method is based on the socalled law of propagation of uncertainty, which in essence is the approximation based on the first-order Taylor series expansion. The second presented method is based on the Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

Archaeological research, especially field excavation research, despite due diligence, may lead to irreversible damages. That is why preparing detailed and comprehensive documentation is essential part of archaeological work before and during exploration of archaeological sites. In such cases, unmanned aerial vehicles (UAVs) are currently widely used to register state of preservation of archaeological sites and objects. Data collected by UAV allows to generate digital terrain models (DTMs) and orthomosaics. In turn, they (along with results of other research, such as geophysical surveys) form the basis for selection of excavation areas. In this paper authors present process of DTMs and orthomosaics of archaeological sites generation without using UAV. The studies in order to provide documentation of two archaeological sites in southern Jordan: the ancient city of Tuwaneh and the Roman fort in Dajaniya, were conducted as a part of the BARI -Buildings ARcheology Inventory project, which was carried out in cooperation with the Institute of Archeology of the Jagiellonian University in Cracow. Unfortunately, due to formal regulations using UAV in the territory of Jordan was not possible (no permission to import and use UAV from the Jordanian government administration). Therefore, it was decided to collect survey data with the use of alternative method – GoPro action camera mounted on boom. In this article, authors describe the full methodology of conducting measurements and the results of tests aimed at determining the accuracy of generated photogrammetric products. Optimization of ground control points was discussed along with amount of images collected. Referential measurements were carried out by means of FARO FocusM70 laser scanner and close range photogrammetry. [ABSTRACT FROM AUTHOR]