To explore the deformation and gas seepage rules of coal and rock under variable axial compression loadings

with coal pulverized coal specimen pressed for the study

using triaxial stress thermal-hydro-mechanical coal containing gas permeability system

five kinds of coal in different axial compressive loading paths under three axial compressions and gas seepage test were carried out. The results show that: Deformation of coal body can be divided into four stages: compaction

stable development

non stable fracture development and fracture. Strain rate of change of the specimen compaction stage mainly related to open structure surface and the fracture and regardless of the axial compressive load range; the stable development stage

while the axial compression loading rate is different

but in the axial compression loading the same interval

variation of axial strain rate is basically the same. The coal permeability and axial compression loading rate is negatively correlated with changes during the variable axial compression loading early stage and the permeability variation rate and axial compressive loading rate and little correlation in the late period. The above conclusions have important significance to guide the monitoring and early warning of rockburst and coal and gas outburst.