Considering that the unloading experiment can truely reflect the mechanical behavior of rock mass, the triaxial loading and unloading test of rock mass containing precast jointed was carried out. The results show that the destruction of the jointed rock mass is not a one-off damage compared with intact rock specimens, there is an obvious stress drop phenomenon in the process of test, and its brittle characteristic is not obvious. The ultimate strength of jointed rock is significantly less than that of the intact rock specimens, the average decrease of peak intensity of the intact rock and jointed rock in unloading test are 9.13% and 18.81%, respectively,compared with the normal triaxial strength, which suggests that the damage of jointed rock occurs more often under unloading test. Jointed rock has many times of stress drop phenomenon in the rupture process, acoustic emission ringing count rate would abruptly increase in every time that stress drop occurs. In addition, the damage degree of jointed rock is weak compared with intact rock in unloading tests.%基于节理岩体在卸荷作用下的力学状态能更真实地反映实际工程中岩体的力学行为,对含预制节理岩体进行三轴压缩及卸荷破坏声发射试验研究.研究结果表明:与完整岩样相比,节理岩样的破坏并不是一次性的,存在明显的应力降现象,其脆性特征与完整岩样相比不够明显;在卸荷试验中,节理岩样极限强度明显比完整岩样的小,与常规三轴强度相比,完整岩样和节理岩样卸围压试验的峰值强度平均降幅分别9.13%和18.81%,表明在卸荷试验中节理岩样更易发生破坏;节理岩样在破裂过程中发生多次应力降,每次应力降发生时,声发射振铃计数率突增,此外,节理岩样在卸荷试验中的破坏程度与完整岩样相比较弱.
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