饱水粉砂岩破裂过程中红外温度突变异常

Abnormality of infrared temperature mutation in the process of saturated siltstone failure

岩石加载条件下微破裂的发育将引起岩石表面红外温度发生变化,临破裂岩石微破裂的加剧发育可能导致其红外温度发生突变异常。为从红外温度突变的角度探寻岩石受力灾变前兆,进行了粉砂岩单轴压缩红外-声发射实验,对热图像序列按1 s/帧进行重采样与差分处理,并从升温和降温2个过程、幅值和规模2个角度对受力岩石的红外温度突变特征进行研究。结果表明,临破裂粉砂岩存在红外温度突变异常前兆,包括突升异常、突降异常前兆与突变极值异常、突变点量异常前兆;对于低强度的粉砂岩,因张破裂较为发育而导致红外温度突降异常前兆的出现概率普遍高于突升异常前兆;突升异常、突降异常前兆之间具有负相关性,突变极值、突变点量异常前兆之间具有正相关性,4种形式的红外温度突变异常前兆既能相互补充,又能相互验证。

The development of rock micro rupture is aggravated when rock failure is approaching under loading, which may cause the abnormality of infrared temperature mutation. In order to investigate the rock catastrophe precursors in terms of infrared temperature mutation, the infrared and acoustic emission experiment was carried out under the condition of uniaxial compression, with the thermal image sequence being resampled and differential treatment being conducted according to 1 second per frame of treatment. From two processes of heating and cooling, and the two angles of amplitude and size, the infrared temperature mutation characteristics of siltstone was studied. The results show that the approaching failure siltstone infrared temperature mutation abnormal precursory exists, including abrupt rise abnormality, abrupt fall abnormality, mutation extreme abnormality and mutation point amount abnormality. For low-intensity siltstone, the occurrence probability of infrared temperature abrupt fall abnormal omen is generally higher than abrupt rise abnormal omen. The relationship of abrupt fall and abrupt rise abnormal omen of infrared temperature is generally negative correlation, and there is a positive correlation between mutation extreme abnormal omen and mutation point amount abnormal omen. The four forms of infrared temperature mutation abnormal omen not only can complement each other, but also can verify each other. © 2015, China Coal Society. All right reserved.