Author

Yujia Lian

Date of Graduation

2017

Document Type

Thesis

Degree Type

MS

College

Statler College of Engineering and Mineral Resources

Department

Mining Engineering

Committee Chair

Yi Luo

Committee Co-Chair

Keith A Heasley

Committee Member

Mark F Sindelar

Abstract

Safe and economic longwall coal extraction requires a good knowledge of overburden strata characteristics and understanding of overburden strata movement in response to the full extraction mining. Subsidence induced overburden movement will affect overlying mining, surface and subsurface water bodies, and methane emission and migration in the overburden strata. Therefore, an understanding of subsurface strata movement is essential for optimal layout of multiple seam mining, protecting water resources, and designing of gob hole patterns for longwall degasification.;Physical simulation experiments play an important role in mining engineering research by allowing visual observations of strata movement in the mining process. In recent years, the advantage physical simulations has supplemented to weakness of computer simulation in some aspects. Some advanced research results in ground control have been obtained through physical simulation, and the findings include key hinged-beam theory, the formation of fractured zones with different permeability in overlying strata.;To improve the method of obtaining and processing measured data during a simulation experiment, a photogrammetry program for capturing and processing the data from physical modeling of mine subsurface subsidence has been developed. The program can capture the observation or measurement points accurately by simply clicking a mouse on an image of the experiment. Four point geometric affine transformation was used in the program to make corrections to images with relation to the camera's change of position over the experiment process. Finally, the program can generate the subsurface subsidence database and export to an spreadsheet file for further data analysis. Subsurface displacement, horizontal strain, and void ratio can then obtained from the data generated by the program. Overall, the program provides an alternative, rapid approach to capturing and processing subsurface subsidence data from a physical simulation model, and introduces a new way to help minimize the error brought by both human and measurement devices.

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