高温下花岗岩的细观结构与声发射特性研究

利用LEICA DM4500P偏光显微镜对实时温度作用下山东临沂花岗岩的细观形态进行了观测，结合其在高温下单轴压缩与声发射检测试验结果，对不同温度下花岗岩的强度和声发射与细观结构形态关系进行了初步的探讨。研究表明，高温下花岗岩细观结构形态的变化主要体现在不同温度下裂纹萌生及扩展速度的不同；随温度的升高，花岗岩内部形成的裂纹越多，内部损伤越严重，单轴压缩下其声发射活动越频繁；花岗岩的力学特性及声发射特征与岩样内部裂纹网络的形成具有对应的关系，裂纹扩展缓慢则其峰值应力曲线和振铃累计数曲线走势平稳，而裂纹网络急剧扩展则峰值应力曲线和振铃累计数曲线出现拐点导致突变。通过观测岩石在热作用下内部结构形态的变化，以期推断其在热破裂过程中物理力学特征参量发生变化的原因。

Research on characteristics of mesostructure and acoustic emission of granite under high temperature

The meso-morphology of granite from Shandong Linyi has been observed under the real-time temperature using polarizing microscope LEICA DM4500P. The relations of microstructure morphology with intensity and acoustic emission of granite have been carried on the preliminary discussion by combined with results of axial compression and acoustic emission detection test at different high temperatures. Research results show that the changes of mesostructure and morphology of granite under high temperature are mainly embodied in crack initiation and different propagation speeds at different temperatures. With the increase of temperature, the more internal crack formation and internal damage for granite, and the more frequent acoustic emission activity of granite under uniaxial compression. The mechanical properties and acoustic emission characteristics of granite with the formation of internal crack network of granite has a corresponding relationship. The peak stress curve and ringing cumulative number curve of granite have stable trend when crack expansion is slow. While crack network expansion is rapid, the peak stress curve and ringing the cumulative number curve of granite will appear inflection point and cause mutation. It is expected to infer the change reason of physical and mechanical characteristic parameters for rock in the thermal cracking procedure through observation changes of rock internal structure under heating states.