Bezpieczeństwo Pracy i Ochrona Środowiska w Górnictwie Number 12/2015

The subsidence and strains caused by underground mining has been predicted and analyzed for years by mining companies. This analysis should be used to protect the private properties and technical infrastructure in mining areas. The presented paper deals with the issues of land subsidence prediction regarding to computer software development. Authors proposed using some mobile devices to predict the subsidence components or to download their values directly from the servers. Two computer applications were presented and discussed in the paper. The possibilities of the mobile devices in assessment of mining induced damages were introduced on the case study in copper ore mining area.

This paper presents the results of numeric modelling of the ground stress and displacement distributions within a rock mass, caused by thermal stressing during underground coal gasification. The inputs for the model were the laboratory experimentation results obtained for geo-mechanical properties of rock around a reactor with a predefined geometrical form. The calculation inputs included the results of tests of mudstone characterised by low compression strength for mono-axial compression (in air-dry state), and medium-grained sandstone with moderate compression strength, with both rock types sampled from the Chwałowice basin deposits. The rock samples were heat treated at temperatures between 100 and 1200C and had the following parameters determined: resistance to mono-axial compression and Young's modulus. The numerical calculations were processed using the FLAC3D software suite by the finite difference method. There was a total of two numerical calculation variants: (1) without and (2) with changes in geo-mechanical properties caused by temperature (from the laboratory research), for two lithological systems. The modelling investigation results have proven that it is feasible to consider changes in rock geo-mechanical parameters in relation to the temperature acting on the rock, and thus to precisely represent the process of underground gasification and its effects on the stresses and displacement around the gasification reactor chamber. The inclusion of the changes in geo-mechanical parameters had a significant effect on the calculated stresses and displacement of the rock mass.

The aim of this article was to show the effects of soil remediation, that was degraded by mining related activities. The tasks shown in the article are being executed or are already fulfilled, by the coal mines on the property of OUG in Katowice (mines of KHW S.A, KW S.A. and Tauron Wydobycie S.A). By carrying out the post-mining area remediation tasks, mines KHW S.A. have restored the usable properties of the terrain, with the total area of 157ha, transforming them mostly into forest and forest-park terrain. Thanks to that, the landscape and ecosystem qualities have been improved. An interesting solution in the area of remediation and grounds development is also a project related to the development of gangue in Lędziny carried out by KW S.A. KWK “Ziemowit”, and the concept of development of the mine waste disposal facility in Libiąż, created by TW S.A ZG “Janina”. Executing the above plans will allow to create green terrains with varied landscapes and interesting places, where in the ambient of nature, local inhabitants will be able to spend their free time with family and friends.

Dimensional consistency, testing repeatability and uniform testing schedule are the key issues in assessment of products and practical solutions. Standard requirements, which in the case of lack of European regulations are defined on the local national level, are the tool in proper assessment of products. The results of the standardization work of Technical Committee 285 in defining the technical requirements for the spraying nozzles used in the machines operating in underground mine workings are described.