Porosity Analysis Based on CT Images of Coal Under Uniaxial Loading

Lingtao Mao, Peng Shi, Hui Tu, Liqian An, Yang Ju, Nai Hao

Department of Mechanics, Beijing Institute of Technology, Beijing,China.
National Engineering Research Center for Coal Gas Control, Huainan, China.
State Key Laboratory of Coal Resources and Safe Mining, China University of Mining & Technology, Beijing, China.

DOI: 10.4236/act.2012.12002                

Abstract

According to the character of CT image, surface porosity and voxel porosity are defined from pixel and voxel scale respectively. Digital Terrain Model (DTM) method is applied to calculate the surface porosity, and the method of voxel porosity is also presented based on Industrial CT grey image. With proposed methods, CT images of coal under differ-ent uniaxial loading are analyzed, and the relation curves between two kinds of porosity and stress separately are shown. All of these porosities reflect inner damage of coal. The surface porosity shows the pore with pixel scale, and voxel porosity denotes the pore inner pixel. The voxel porosity reflects the character of CT image better.

Keywords

Porosity Analysis; Coal Sample; ICT Image; Surface Porosity; Voxel Porosity; Uniaxial Loading

Conflicts of Interest

The authors declare no conflicts of interest.

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