To better understand the issues about the surface movements in the coal mining region Lugau-Oelsnitz, Germany, small-scale numerical models are firstly utilized for verifications via analytical solutions, to explore the simulation schemes, and for parameter sensitivity analysis. 1D rock column numerical models shows that simulated surface movements are consistent with analytical solutions. The investigations via 2.5D profile numerical models also show that uplift is linear related to water level rise under confined mine water conditions, while a quadratic function is valid for unconfined mine water. Geodetic survey in the Lugau-Oelsnitz district shows that at the end of the active mining period (1844 to 1971), general subsidence is about 5 - 10 m, with a maximum of 17 m in the southern mining area. General uplift velocity after abandoned mine flooding between 1972 and 2014 is about 0.5 - 2.0 mm/year. Based on numerical simulation results, predicted general uplift velocity vary between 0.5 - 3.0 mm/year, while maximum uplift position is moving toward south.:1 Introduction
2 State of the art
2.1 Overview
2.1.1 Coal mining induced settlements
2.1.2 Flooding induced uplift
2.2 Approaches to predict subsidence
2.2.1 Empirical approaches
2.2.2 Influence function methods
2.2.3 Physical models
2.2.4 Numerical simulation methods
2.3 Approaches to predict uplift
2.3.1 Empirical approaches
2.3.2 Numerical simulation methods
2.4 Comparison and conclusions
2.4.1 Comparison of research methods
2.4.2 Conclusions
3 Numerical simulation approaches
3.1 Continuum mechanical simulations with FLAC3D
3.1.1 Mining induced subsidence
3.1.2 Flooding induced uplift
3.2 Discontinuum mechanical simulations with 3DEC
3.2.1 Self-weight induced settlement in jointed rock column model
3.2.2 Uplift for jointed and fully saturated rock column
3.3 Parameter sensitivity study
3.3.1 Parameter effect on subsidence
3.3.2 Parameter effect on uplift
3.4 Interface and volume element representation of faults
3.4.1 Simulation schemes
3.4.2 Parameter sensitivity analysis of fault
3.4.3 Discussion
3.5 Conclusions
4 Case study: Coal mining region Lugau-Oelsnitz
4.1 Background information
4.1.1 Mining background
4.1.2 Geological and hydrogeological situation
4.2 In-situ monitoring data
4.2.1 Groundwater level data
4.2.2 Surface movement data
4.2.3 Discussion of data analysis
4.3 Continuum based numerical modelling
4.3.1 Introduction
4.3.2 Model set-up
4.3.3 Calculation results
4.3.4 Surface movement predictions
4.4 Discontinuum based numerical modelling
4.4.1 Model set-up
4.4.2 Calibration results
4.4.3 Surface movement prediction
4.5 Conclusions
5 Conclusions and prospects
5.1 Conclusions
5.2 Main contributions of thesis
5.3 Inadequacies and prospects
| Identifer | oai:union.ndltd.org:DRESDEN/oai:qucosa:de:qucosa:79854 |
| Date | 12 July 2022 |
| Creators | Zhao, Jian |
| Contributors | Konietzky, Heinz, Otto, Frank, TajduĊ, Krzysztof, TU Bergakademie Freiberg |
| Publisher | TU Bergakademie Freiberg |
| Source Sets | Hochschulschriftenserver (HSSS) der SLUB Dresden |
| Language | English |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, doc-type:doctoralThesis, info:eu-repo/semantics/doctoralThesis, doc-type:Text |
| Rights | info:eu-repo/semantics/openAccess |
| Relation | 1611-1605, 1389431-6 |
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