长江科学院院报 ›› 2010, Vol. 27 ›› Issue (12): 42-46.

• 岩土工程 • 上一篇    下一篇

三轴加卸载条件下岩石损伤破坏机理CT试验分析

刘小红 1,2,晏鄂川 1,朱杰兵 2,汪 斌 2   

  1. 1. 中国地质大学(武汉) 工程学院,武汉 430074;2. 长江科学院 水利部岩土力学与工程重点实验室,武汉 430010
  • 出版日期:2010-12-01 发布日期:2012-09-05

CT Test Analysis on Rock Breakage Mechanism UnderTriaxial LoadingUnloading Condition

LIU Xiao-hong 1,2,YAN E-chuan 1, ZHU Jie-bing 2,WANG Bin 2   

  1. 1.Faculty of Engineering,China University of Geosciences(Wuhan), Wuhan 430074,China;2. Key Laboratory of Geotechnical Mechanics and Engineering of the Ministry of Water Resources, Yangtze River Scientific Research Institute,Wuhan 430010,China
  • Online:2010-12-01 Published:2012-09-05

摘要: 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。

关键词: CT试验 , 三轴压缩 , 加卸载 , 损伤演化 , 岩石力学

Abstract: 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.

Key words: CT test;triaxial compression ,  , loadingunloading ,  , damage evolution  , rock mechanics

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