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In order to reveal the mechanical properties and damage mechanism of coal with parallel multibedding under stress disturbance, the raw coal samples with parallel multibedding were selected. The uniaxial compression and acoustic emission damage measurement were carried out using the coal-rock mechanics damage coupling test system, revealing the bedding effect of coal deformation-damage failure differentiation under different loading methods; based on the test results, a coupling characterization model of mechanical damage of coal and rock with parallel multibedding is established. The results show that (a) the acoustic emission of raw coal samples under different loading modes has obvious differentiation characteristics of bedding effect. When the vertical bedding is loaded, the peak stress of raw coal samples is relatively high and the acoustic emission activity period is relatively long; when the parallel bedding is loaded, the active degree of acoustic emission is relatively strong, and there is an obvious mutation period after the acoustic emission enters the acute period. (b) Under different loading modes, the difference in the influence of bedding on the fracture evolution of raw coal specimens is mainly concentrated before the stress turning point. In stage I, the acoustic emission b value of raw coal specimens decreases first, then becomes stable under vertical bedding loading, and decreases under parallel bedding loading; in stages II and III, the acoustic emission b value of raw coal samples showed the same change trend under different loading modes. (c) Combined with the basic principle of continuous damage mechanics and based on the difference of bedding effect, the relationship between cumulative acoustic emission ringing count and stress and damage variable of the raw coal samples was established. The rationality and effectiveness of the model are verified by experiments.

By means of field observation, theoretical analysis, numerical simulation etc., the zonal failure characteristics of stope floor and the asymmetric failure mechanism of floor roadway were studied. The study results showed that the floor roadway rib near the residual coal pillar has lower ultrasonic wave velocity than the other rib, with more developed fissures. The deflection is larger in the middle of the roadway roof and the tensile failure is the dominant one, and as a result, the ultrasonic wave velocity in the middle of the roadway roof is lower than that on both sides; under the advance abutment pressure, there was no large-scale failure in stope floor, while in the compaction stability stage, a large range of compressive shear failure was found in the residual pillar floor. The mining-induced unloading causes a large tensile stress at the internal defects of the floor rock in the goaf, which leads to the goaf floor dominated by tensile failure; the numerical simulation results revealed that there is a spherical stress concentrated shell and spherical stress relief body in the goaf floor. The shape and range of tensile plastic zone of the goaf floor correspond to the spherical stress relief body, and the shape and range of shear failure zone of the floor correspond to the spherical stress concentrated shell; One side of the floor roadway is close to the rock mass with compressive shear damage and the other side close to the rock mass with unloading-induced tensile damage, which is the main reason for the asymmetric failure of the roadway. According to the asymmetric failure mechanism of the floor roadway, asymmetric support measures are proposed for the roof and floor respectively.