不同温度下绿砂岩微观结构及热损伤规律试验研究

Experimental Study on Microstructure and Thermal Damage Law of Green Sandstone at Different Temperatures

为探讨不同温度作用下绿砂岩微细观结构变化及热损伤规律,采用扫描电子显微镜等试验手段,对热处理后的绿砂岩表观形态及微观结构变化进行研究。结果表明:温度对绿砂岩的微细观结构具有重要影响。试件表观形态变化的临界温度为400℃;当温度高于600℃时,砂岩内部的微裂纹数量明显增加,裂隙网络的贯通性增强;1000℃时微裂纹增加最为显著。绿砂岩微观结构变化的主要原因是内部矿物颗粒的性质不同,导致不同温度下产生不同的微观变化。

In order to explore the microstructure changes and thermal damage law of green sandstone under different temperatures,the apparent morphology and microstructure changes of green sandstone after heat treatment were studied by means of scanning electron microscope and other experimental methods.The results show that temperature has an important influence on the microstructure of green sandstone.The critical temperature of the apparent morphological change of the specimen is 400℃.When the temperature is higher than 600℃,the number of microcracks inside the sandstone increases significantly,and the connectivity of the fracture network increases.The increase of microcracks is the most significant at 1000℃.The main reason for the change of the microstructure of the green sandstone is that the different properties of the internal mineral particles lead to different microscopic changes in different temperature reactions.