Abstract: Uniaxial compression tests with different loading rates were conducted on standard samples of combination samples of “roof-coal” structure caused by coal bump. By analyzing the stress and strain development process and
acoustic emission response characteristics under different loading conditions, the basic damage modes and the possible conditions of abrupt change were obtained. The deformation and failure of the samples experienced obvious development stages with the increase of loading rate, namely progressive shear failure, splitting failure and structural failure. Sudden holistic instability eventually occurred with the weakening of internal bearing structure. Through analyzing the relative slip characteristics of composite structure and the geological conditions and mining effects of typical mines, the failure mode of coal bumps under the condition of compound coal-rock is clarified. The results offer reference for targeted failure control.

Key words: coal bumps, compound coal-rock, stress condition, burst characteristics, deformation characteristics, failure mode of coal-rock