Vertical pit-shafts, differing with their uniqueness and importance for production complex of mining enterprise, demand permanent searching and developing efficient decisions as for intensifying their production and overhaul exploitation [1], which is, in its turn, crucial scientific and technical task as regards development of coal mining in Ukraine.
At present stage of studying exploitation conditions for Donetsk coal field substantial knowledge is gained about those peculiar ways ground pressure manifests itself in excavations incl. vertical shafts.
Constructing vertical shafts appears one of chief parts in technical system of mining enterprise. During the construction period the shafts are located on critical path, works on striking and preparing the deposit, assemblage of tunnelling and winning equipment are carried out via them, thus they influence the terms and costs of the whole building process a lot.
During the exploitation period the shafts are chief permanent workings, which serve for excavating minerals and rocks, lowering and lifting people, materials and equipment, for ventilation and laying out cables and piping etc. Reliability and efficiency of the whole mining complex depend on functionality of the shafts.
Construction and maintenance of vertical shafts is carried out on the grounds of normative documents worked out by leading organizations and specialists of the branch. However support damages and equipment failures often occur through exploiting vertical shafts (53% deep shafts and 42% medial shafts). Analysis showed that 38-50% damages are caused with technological projects deviations made in process of drilling-and-blasting the shafts and cast-in-placing in accordance with combined scheme.
Goals and tasks of the research
The goal of master's research is increasing efficiency of lining and equipment of vertical shafts, considering expected radial deviations of lining walls from normative figures, shaft section form on light and raising waterproofing features of shaft support to increase the term of its exploitation.
Idea of the research. Determining parameters of cast concrete (ferroconcrete) lining on the grounds of mining logs, considering expected deviations of the lining walls from project figures, change of section form in light and lining thickness as regards technological peculiarities of the work, diameter in light and shaft depth.
In research process the following tasks must be solved:
- Analysing lining and equipment condition of vertical shafts in Donbass coal mines.
- Researching factual deviations of shaft section parameters from project figures in GOAO Trest Donetskshakhtoprokhodka.
- Researching the way these deviations influence the equipment condition. Researching stressedly-deformed condition of vertical shaft lining on numerical models.
- Working out PC model of the "equipment-lining-stratum" to ground the work of vertical shaft lining parameters.
- Laboratory research of watertightness of cast concrete lining.
- Working out technological regulations of usage of waterproofing materials for protection of cast concrete lining.