Original scientific paper

https://doi.org/10.17559/TV-20190115040502

Goaf Compaction Evaluation Based on Integrity and Permeability Measurement of the Overburden Strata

Xiaorong Zhai ; (1) School of Earth and Environment, Anhui University of Science and Technology / (2) Key Laboratory of Mine Geological Disaster Prevention and Environment Protection of Anhui Higher Education Institutes, Room 312, No. 168 Taifeng Road, Tianjiaan district
Guangtao Wang ; School of Earth and Environment, Anhui University of Science and Technology, China Room 108, No. 168 Taifeng Road, Tianjiaan district, Huainan, Anhui Province, China
Jiwen Wu ; School of Earth and Environment, Anhui University of Science and Technology, Room 314, No. 168 Taifeng Road, Tianjiaan district, Huainan, Anhui Province, China
Yaoshan Bi ; School of Earth and Environment, Anhui University of Science and Technology, Room 107, No. 168 Taifeng Road, Tianjiaan district, Huainan, Anhui Province, China

Abstract

Groundwater outbursts from coal mine goafs, which are widely distributed in China with the increase in the number of abandoned coal mines, demonstrate an impartible relationship with the permeability of goaf overburden strata. A research on rock mass integrity and permeability characteristics of goaf overburden strata is necessary to assess waterinrush risk induced by goaf water. Two goafs in two adjacent coal mines located at the Huaibei mining area in the Anhui Province of China were considered as the research targets. A ground exploration hole was conducted in each goaf. The rock mass integrity and fracture development of goaf overburden strata were determined on the basis of rock quality designation (RQD) and borehole television. The permeability of goaf overburden strata was measured by performing a field packer test. Results are as follows: (1) The fracture development of the borehole wall of the production mine is favorable, and a water drenching phenomenon occurs. The RQD is approximately 20.8–35.6%, which indicates that the integrity of the goaf overburden strata of the production mine is poor. The unit water inflow (q) is 0.133 L/s.m, and the average permeability coefficient is 0.26 m/d, which reveals that the goaf overburden strata of the production mine exhibit medium water abundance and permeable strata. (2) The overburden strata parameters of the abandoned mine goaf are as follows: the q is 0.012–0.014 L/s.m, and the average permeability coefficient is 0.005 m/d, which suggests that the goaf overburden strata exhibit poor water abundance and low permeable strata. The results demonstrate that the overburden strata compaction of the two goafs is different and the results can provide a reference for adjacent mines to access the water inrush risk induced by the goaf water of the abandoned coal mines.

Keywords

overburden strata; packer test; permeability coefficient; water inrush

Hrčak ID:

219544

URI

https://hrcak.srce.hr/219544

Publication date:

24.4.2019.

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