深部复杂环境中热力条件下岩石破裂机理是当前研究热点之一.采用统计方法对工程温压内花岗岩单轴、三轴压缩、三轴卸荷试验条件下宏观破裂特征进行了分区分析,并探讨了其机理.结果显示:低温低围压区(20～40℃、0～5MPa)岩样以剪切破坏为主,伴有次级张拉裂缝.低温高围压区(20～40℃、15～30MPa)岩样为剪切破坏,且随着围压升高,出现多个剪切破裂面.高温低围压区(60～130℃、0～5MPa)岩样为张拉破坏.高温高围压区(60～130℃、15～30MPa)岩样为剪切破坏.围压增加试样峰值强度明显增加,升温试样峰值强度变化不大.研究表明:在工程温压内,岩样性能主要受围压影响;温度对岩样破裂方式有一定的影响,尤其是低围压区.针对温压耦合条件,传统的考虑单一变量的分析结果偏于片面,而分区考虑双变量的分析结果更为客观合理;宜建立多破裂面复合型模型探讨其发生机理.%The mechanism of rock fracture under deep complex environment, especially thermal-mechanical coupling conditions, is one of the hotspots in the current research.Combining testing results of uniaxial, triaxial compression and triaxial unloading tests under engineering temperature and pressure, the macro fracture characteristics and mechanism of granite were analyzed from the view of statistics.The results show that at low temperature and low confining pressure area (20～40℃, 0～5 MPa), the rock samples are mainly shear failure, accompanied by secondary tensile cracks.At low temperature and high confining pressure area (20～40℃, 15～30 MPa), rock samples are shear failure, and with the increase of confining pressure, there are more shear fracture surfaces.At high temperature and low confining pressure ar-ea (60～130℃, 0～5 MPa), rock samples are tensile failure.At high temperature and high confining pressure area (60～130℃, 15～30 MPa), the rock samples are mainly shear failure.The peak strength of the samples increased sig-nificantly with the increase of confining pressure, while little changes with the increasing of temperature.The results show that under the engineering temperature and pressure the performance of rock samples are mainly affected by the confining pressure.However, the temperature has a certain influence on the fracture mode, especially in the low confi-ning pressure area.For thermal-mechanical coupling conditions, the traditional single variable analysis' results are bi-ased, while considering two variables analysis's results would be more objective and reasonable.It would be better to es-tablish a multi-fracture surface to explore its mechanism.
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