The 4th International Symposium on Mine Safety Science and Engineering (ISMSSE2018)

324 / 2018-05-04 16:08:47

Experimential study on seepage and acoustic emission characteristics of similar materials of outburst coal

Coal and gas outburst,similar material, acoustic emission, seepage characteristics

Gas of Coal Mine & Coal and Gas Outburst > Coal and gas outburst

In order to develop a similar material which is more closely related to the raw coal, selecte coal powder as aggregate, cement as binder, activated carbon, sand and water as the auxiliary materials to make the solid gas coupled material.The YYW -Ⅱ acoustic emission testing instrument and heat-fluid-solid coupling seepage device are used to conduct three-axis servo conventional triaxial and triaxial unloading confining pressure to test acoustic emission and seepage characteristics of similar material. The results show there is a close relationship between acoustic emission energy release and fracture development during uniaxial fracture; the acoustic emission energy release can be divided into five phases: the phase of energy storage, the stage of flexible energy release, the stage of broken energy release, the stage of repeated broken energy release, and the stage of energy balance. Furthermore, In conventional triaxial test, permeability decreases firstly, and close to stabilize with the with the increase of axial stress and strain, before failure. The permeability characteristics of similar material with raw coals’ are basically identical. In triaxial unloading confining pressure test, the permeability of similar material decrease obviously with the increasing of axial compression. And the reduce variation is more than conventional triaxial test. The experimental results provide a test basis for the solid-gas coupled physical simulation and the coal and gas outburst physical simulation.