煤样轴向应力加载−水压渗流作用下裂隙(孔隙)发展直接影响煤样试件的力学指标与渗流特性，文中通过理论解析与力学试验方法，分析了煤样试件裂隙(孔隙)主导下渗透率与声发射分形维数、振铃计数响应关系，建立了水力耦合作用下煤样声发射分形−渗透率模型，开展了不同围压(2～5 MPa，Δp_w(渗透压)/p'_c(围压)=0.75)下水力耦合煤样渗流试验，分析了不同围压(水压)下煤样试件的力学行为、声发射规律与渗流特征，探讨了不同围压下煤样试件的强度提升特点与破坏形态−声发射定位关系，验证了水力耦合下煤样试件的声发射分形−渗透率模型合理性。结果表明：煤样试件渗流试验中裂隙(孔隙)变化与声发射振铃具有一致性，裂隙(孔隙)扩展与声发射分形维数、渗透率密切相关，声发射分形、渗透率可用体积应变表征，基于声发射分形的水力耦合下煤样试件的声发射分形−渗透率模型可采用2段式数学模型解析；煤样渗流全应力−应变过程中渗透率表现为短时减少—长时缓慢增加—急速增加—小幅回落过程，振铃计数呈快速增加—减少—增加—减少波浪型发展，渗透率最小值滞后体积应变压缩与膨胀临界点，最小渗透率变化在0.124×10⁻¹⁷～1.250×10⁻¹⁷m²；随着围压(2～5 MPa)增加，煤样峰值偏应力、峰值轴向应变与峰值体积应变均呈增大趋势，线性特征显著，煤样峰值渗透率滞后峰值强度呈减小趋势，减幅达到93.34%，最大声发射振铃计数(对应峰值强度位置)表现为增加趋势；水力耦合下煤样试件有效黏聚力和有效内摩擦角分别提高到6.511 6 MPa与36.56º，随着围压(2～5 MPa)增加，煤样试件的声发射信息由单斜面向不规整斜面过渡，主控破裂面角度由小角度向高角度转变，失稳由单块体剪切变为多块体压缩形态，试件破裂可采用声发射定位振铃计数表达；煤样试件声发射分形−体积应变、渗透率与体积应变、分形与渗透率3个试验曲线与理论曲线较为吻合，围压2～5 MPa试件压缩阶段相关性分别在0.882～0.999、0.950～0.998与0.849～0.997之间，围压2～5 MPa试件膨胀阶段相关性0.937～0.996、0.891～0.998与0.873～0.966之间。

The fracture (pore) development of coal specimen under axial stress loading and hydraulic permeability affects directly the mechanical indexes and the permeability characteristics. In this paper, using theoretical analysis and mechanical test methods, the relationships between permeability and fractal dimension, ringing count response under coal specimen fracture (pore) were analyzed, and the acoustic emission fractal-permeability model of coal specimens under hydraulic-loading coupling were established. The permeability experiments of coal specimens with hydraulic-loading coupling in different confining pressures (2−5 MPa, Δp_w/p'_c=0.75) were carried out, and the mechanical behavior, permeability characteristics and acoustic emission rules of coal specimens in different confining pressures (water pressure) were analyzed, and the relationship between the failure morphology of coal samples under different confining pressures and the acoustic emission positioning was discussed. The strength enhancement characteristics and the relationships between failure pattern and acoustic emission location of coal specimens under confining pressures were discussed. The rationality of the fractal-permeability model of coal specimens under hydraulic-loading coupling was verified. The results showed that the fracture (pore) change of coal specimen was consistent with acoustic emission ringing, the fracture (pore) development was closely related to the fractal dimension and the permeability, and the acoustic emission fractal and permeability could be characterized by the volume strain in the permeability experiments. The acoustic emission fractal-permeability model of coal specimen under hydraulic-loading coupling could be analyzed by a two-stage mathematical model. The permeability of the coal specimen showed the process of short-term decrease, long-term slow increase, rapid increase and slight decline, and the ringing count showed the wave-like development of rapid increase - decrease - increase - decrease during the total stress-strain process of coal specimen, the minimum permeability lagged behind the critical point of volume strain compression and expansion, and the minimum permeability varied from 0.124×10⁻¹⁷ m² to 1.250×10⁻¹⁷ m². With the increase of confining pressure (2−5 MPa), the peak deviating stress, peak axial strain and peak volume strain of coal specimen all showed an increasing trend, the linear characteristics were significant, the lag of peak permeability behind peak strength showed a decreasing trend, the reduction reached 93.34%, and the loudest ringing count (corresponding to the peak strength) showed an increasing trend. The effective cohesion and the effective internal friction angle of the coal specimen increased to 6.511 6 MPa and 36.56º under hydraulic coupling, respectively. With confining pressure (2−5 MPa) increase, the acoustic emission information of coal specimen changed from single inclined plane to irregular inclined plane, the angle of the main fracture plane from small angle to high angle, and the instability mode from single block shear to multi-block compression, and the specimen fracture could be expressed by acoustic emission positioning ringing count. Three experiment curves of acoustic emission fractal-volume strain, permeability and volume strain, and fractal and permeability of the coal specimens were consistent with the theoretical curves, the correlation during compression stage with confining pressure 2−5 MPa was 0.882−0.999, 0.950−0.998 and 0.849−0.997, respectively. The correlation during the expansion stage was 0.937−0.996, 0.891−0.998 and 0.873−0.966, respectively.