Abstract
To understand the change in overburden structure after coal seam group mining, we investigated the overburden characteristics and bearing capacity of abandoned coal mines in a coal seam group. We provide a theoretical basis for the construction and utilization of a coal mining subsidence area under a complex geological environment. This paper takes the construction project of Zhongtie Huizhi Square in Zhangqiu District, Jinan City, Shandong Province as the engineering background. According to the occurrence conditions of the study area, theoretical analysis, similar simulation, numerical simulation, and engineering practice verification are used. The overburden structure characteristics of abandoned mines in a shallow-buried coal seam group were studied. The results show that the development height of the water-carrying fractured zone after the mining of the 3#, 4#, and 9# coal seams is 17 m, 19.5 m, and 27.1 m, respectively, which shows that the height of water flow in the fractured zone is proportional to the buried depth of the coal seam after coal seam mining. After the model is set aside for three months, the degree of development of the residual fracture in the goaf is analyzed, and the distribution law of residual porosity in the longwall old goaf of a shallow-buried multiple coal seam is obtained. The development rate of residual fissures on both sides of the goaf is between 20.31% and 42.31%. The residual fracture development rate in the middle is relatively small, being between 8.21% and 18.53%. We comprehensively analyzed the characteristics of overlying strata in the abandoned mine under actual stratum conditions, and compared the empirical calculation results, theoretical research, similar simulation, and numerical simulation results in the specification with the engineering practice to prove the reliability of the research.
Funder
National Natural Science Foundation of China
Shandong Provincial Natural Science Foundation
China Postdoctoral Science Foundation
Subject
Energy (miscellaneous),Energy Engineering and Power Technology,Renewable Energy, Sustainability and the Environment,Electrical and Electronic Engineering,Control and Optimization,Engineering (miscellaneous),Building and Construction
Reference43 articles.
1. Characteristics and trends of coal mine safety development;Li;Energy Sources Part A Recover. Util. Environ. Eff.,2020
2. Distribution of rare earth elements in fly ash derived from the combustion of Illinois Basin coals;Hower;Fuel,2021
3. Geochemistry and mineralogy of coal mine overburden (waste): A study towards their environmental implications;Islam;Chemosphere,2021
4. Characterization of lead-zinc mill tailings, fly ash and their mixtures for paste backfilling in underground metalliferous mines;Behera;Environ. Geol.,2019
5. Prediction of the intensive surface subsidences in mining potash series;Baryakh;J. Min. Sci.,2005