Damage Evolution of Coal Cylinder under Uniform Confinement of Carbon Fiber Sheets
The coal pillar instability disaster is still one of the hot research issues in the safe and efficient mining of coal resources.In order to further study the influence of carbon fiber sheets layers and loading rates on the energy evolution of coal cylinder.The loading rate is divided into four levels:0.01 mm/min,0.1 mm/min,1 mm/min and 10 mm/min,and the layers number of carbon fiber sheets is divided into three categories:0 layer,1 layer and 2 layers.The SAM-2000 rock comprehensive test system was used to perform uniaxial axial compression test on coal cylinder.The test results show that under the same lay-ers of carbon fiber sheets,the higher the loading rate,the more obvious the diffusion of coal dust,the worse the integrity of the coal cylinder,and the stronger the energy release,which belongs to the split-shear composite failure mode.the more layers of carbon fiber sheets,the total energy,elastic energy and dissipated energy at peak gradually increase,the effect of loading rate on the energy of coal cylinder is reduced.According to the energy dissipation theory,the damage factor is proposed,and then the constitutive model is established,and it has a high degree of fitting with the experimental verification.
uniform confinementloading ratescoal cylinderuniaxial compression testconstitutive model
万方数据
维普
