利用RMT150岩石力学测试系统和高分辨率Sensation 40型医用CT机，对恒定围压下不同轴向加载应力阶段的粉砂岩试样进行多次CT扫描试验，得到了不同轴向应力条件下岩石断面的CT图像特征。基于CT数原理，分析了岩石不同应力状态下的损伤演化过程与损伤程度，通过试样CT图像三维重建，较真实地反应了岩石试样细观损伤过程。试验研究表明：试样在试验过程中经历压密、扩容及破坏阶段；岩石压缩损伤演化是有一个相对较长应力段的量变积累过程，裂纹产生及其扩展的质变过程具有突发性；试样破坏后，远离破裂面区域存在“密度回弹”现象。

Using the rock mechanics test system RMT150 and high-resolution CT medical machine, the siltstone specimen CT scan tests under a constant confining pressure and different axial loadings were carried out and clear CT images of rock section were obtained. On the basis of the CT number’s principle, a quantitative analysis on damage evolution and damage degree was performed. The micro-damage process of rock was reflected by the sample’s 3D CT image reconstruction. The test study results showed as follows: The test rock specimen experiences three stages including compaction, expansion and destruction. The compression damage evolution of the rock is a long-time accumulation process and the crack generation and its expansion process manifest a sudden change， and there exists a ‘density rebound’ phenomenon in the region away from fracture plane.