Research of the thermal stability of structure of resin anchoring material based on 3D CT

As a polymer material, UPR anchoring material has pyrolysis at high temperature, which directly affect its mechanical stability. Using micro-CT scans and 3D image reconstruction to analysis pyrolysis characteristics and the pore structure evolution of UPR anchoring material at high temperatures, and the results showed that the thermal decomposition cause obvious changes in internal microstructure at high temperatures; the average gray attenuated 20.7%, pore groups number increased 47.5% and pore group size increased 201.5% between 350 °C and 500 °C; organic cemented body corresponding to attenuation coefficient ranges from 0.0163 to 0.0373, the inner pore increased significantly after organic pyrolysis, and connected with each other to form larger pores group; the pyrolysis critical temperature is 350 °C, pyrolysis affects significantly to the internal structure and the density of the material. Mechanical properties decayed significantly at high temperature (400 °C), compressive strength decreased by 95% and pull-out strength decreased by 68.3%.