Experimental Study on the Permeability Evolution and Gas Flow Law of Post-Strength Soft Coal
Source abstract
Abstract
Permeability is an essential indicator for predicting gas drainage yield and preventing mine gas disasters, which is significantly influenced by the stress paths and the integrity of coal. Conventional research on permeability mainly focused on the permeability evolution of initial undamaged or fractured (prefabricated fractures) coal under various stress paths; little attention has been paid to post-strength coal (stress-induced damage), especially for soft coal. To determine the permeability evolution and gas flow law of post-strength soft coal samples under various stress paths, we used the experimental method combined with the numerical method in this study. The results showed that when the confining pressure and axial pressure of post-strength soft coal samples were unloaded, the permeability increased by 1.25–1.32 times; when the coal samples were loaded into the secondary damage, the permeability first decreased and then increased. The simulation part in this study found that the development of the fracture of coal samples under triaxial compression was divided into four stages. Gas flow law of post-strength soft coal was significantly influenced by fracture locations, and the gas pressure and gas flow field near the fracture were disturbed.
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Research context
OpenAlex topics: Coal Properties and Utilization · Rock Mechanics and Modeling · Hydrocarbon exploration and reservoir analysis
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
School of Civil Engineering, Chongqing University, Chongqing 400045, China
Collaborative Innovation Center for Safe Production and Clean and Efficient Utilization of Coal, Henan Polytechnic University, Jiaozuo 454000, China
School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China
Key Laboratory of New Technology for Construction of China in Mountainous Area, Chongqing University, Chongqing 400045, China
School of Economics and Business Administration, Chongqing University, Chongqing 400044, China
Funding
National Natural Science Foundation of China · Fundamental Research Funds for the Central Universities
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