Abstract:
In order to study the damage evolution law of coal measures rocks under uniaxial compression and its characterization method, three kinds of rocks with different lithology conditions and commonly existing in coal measures rocks are taken as the research object, and different mineral compositions and different microstructures are emphatically discussed, based on the contribution of rock mechanical properties, the special characterization of multi-dimensional acoustic emission parameters is analyzed, and the relationship between damage scale and count and energy parameters is described, based on the theory analysis, the constitutive equation of the response is derived, and the damage evolution process of the bearing body can be further characterized by the combination of the two methods. The results show that the differences of rock micro-morphology and mineral composition of different lithological coal measures directly affect their physical and mechanical properties and damage characteristics under loading. The acoustic emission characteristic ringing counts and acoustic emission energy can effectively represent the damage evolution process during rock loading. The fractal dimension
D of acoustic emission space locating point can reflect the damage and destruction process of rock to a certain extent, but it is greatly influenced by the porosity and density of rock. Based on rock porosity characteristics and acoustic emission cumulative ringing counts during loading, a constitutive model considering initial damage and cumulative damage is established and the influence rule of porosity on damage tensor
Dn is analyzed.