Abstract The evolution characteristics of deformation fields and temperature fields are inspected and analyzed by using the digital speckle correlation method and infrared thermal imager. The test material is a kind of coal and the specimens are loaded by uniaxial test machine. The analytical results show that:(1) The deformation field evolution of coal specimen is divided into two phases:initial uniform deformation evolution to deformation localization at pre-peak loading stage,and deformation concentration in the localization band at post-peak loading stage. (2) The temperature evolution of coal specimen is divided into two phases:temperature rises due to internal particle spacing change caused by thermo-mechanical coupling effect at pre-peak loading stage;temperature decreases due to the tensile-shear effect and the sliding effect of deformation localization band at post-peak loading stage. (3) The temperature change is obvious in the deformation and destruction process of coal specimens;and the temperature evolution characteristics are similar inside and outside the deformation concentration band. The temperature increases at pre-peak loading stage and decreases at post-peak loading stage. The temperature inside the deformation localization band is higher than that outside the deformation localization band.
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Received: 19 November 2012
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