Experimental Study on Deformation Fracture of Coal Samples Under Coupling of Temperature and Pressure

In order to study the characteristics of deformation fracture of coal samples under coupling of temperature and pressure, taking No.2 coal seam of Liuhuanggou Coal Mine in Xinjiang Province as the research object. A programmed temperature rising box was used to treat the coal samples at the temperatures of 25 ℃, 80 ℃, 140 ℃ and 200 ℃. MTS uniaxial compression test and CT scanning test were carried out. The results show that the pore compression stage of coal samples which were treated at 25 ℃ is not obvious; the peak stress and strain of the coal samples treated at 140 ℃ are the largest; the number of micropore fissure of coal sample treated at 200 ℃ is the most, and the peak stress and strain are the smallest. With the increasing of pressure and temperature, the crack growth and shape of crack are obvious.