In the experiments to simulate hydraulic fracturing, monitoring and identification of the hydraulic fractures are fun-damental to the study of the fracture morphology. Large scale hydraulic fracturing experiments were conducted using an indoor tri-axial physical simulation apparatus with 300 mm×300 mm×300 mm shale rock samples. A multi-channel acoustic emis-sion monitoring system was applied, and the acoustic signals induced in the fracturing experiment were collected using acous-tic sensors on the two sides of the sample to set up a 3D dynamic real-time monitoring system. The acoustic positioning tech-nique can clearly recognize the initiation, orientation and morphology of the hydraulic fractures developed. Based on the data analysis of combined acoustic curve and pump pressure curve, the different stages of hydraulic fracture propagation can be monitored in real time, and the intercommunication between hydraulic fractures and natural fractures can be also recognized. The experimental results show that the peak point of the acoustic emission cumulative intensity appears prior to fracture pres-sure point and more signals are received during hydraulic fracture propagation comparison to the initiation of natural fracture. The fluctuation of pump pressure curve after fracturing can be used to recognize the interaction among fractures. The monito-ring results of acoustic emission can be further verified by observing the tracer°s distribution after breaking the rock sample.%水力压裂模拟实验中，对水力裂缝的监测和识别是研究储层裂缝形态的基础。利用室内大尺寸真三轴水力压裂物理模拟装置对300 mm×300 mm×300 mm立方体页岩试样开展体积压裂实验，建立多通道声发射实验监测系统，在试样两个对称侧面布置声发射探头，采集实验过程中裂缝破裂时的声波信号，对裂缝缝网形成过程进行三维动态实时跟踪，可以明确水力裂缝起裂和裂缝扩展形态；再结合声发射计数曲线和泵压曲线可以实时监测水力裂缝不同扩展阶段，判别水力裂缝与天然裂缝相互沟通过程。监测过程发现，声发射累积次数最高点先于破裂压力点出现，水力裂缝扩展接收的声发射信号多于天然裂缝开启过程，地层破裂后泵压曲线的波动可以识别裂缝之间的沟通程度，打开试样观察示踪剂的分布特征进一步验证了声发射监测结果。
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