高温下大理岩受压破坏的细观结构分析  

MESOSTRUCTURAL INVESTIGATION ON MARBLES UNDER UNIAXIAL CONPRESSION AT HIGH TEMPERATURES

作　　者：吴刚[1,2] 翟松韬[3] 李玉寿[2] 吴雪萍[3] 

机构地区：[1]上海交通大学海洋水下工程科学研究院,上海200231 [2]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221008 [3]上海交通大学土木工程系,上海200240

出　　处：《岩石力学与工程学报》2012年第A02期3579-3585,共7页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(40872180);中国矿业大学深部岩土力学与地下工程国家重点实验室开放基金项目(SKLGDUEK1004))

摘　　要：探究高温对岩石的作用机制,对于解决高温岩石工程问题具有重要意义。利用日本日立公司制造S–3000 N扫描电子显微镜对在20℃,200℃,400℃,600℃,800℃高温作用下以及经历400℃,600℃和800℃高温作用冷却后受单轴压缩破坏的徐州大理岩进行表面元素分布测定、表面形貌观察和超微结构分析,以期在细观层次上对大理岩的受压变形、强度及破坏特性等做出机制性的解释。研究结果表明:常温下徐州大理岩的颗粒较为粗大,为典型解理开裂且部分颗粒内及颗粒间存在裂纹,温度升高至800℃时,岩样端口表面碎裂明显、颗粒变小且形态较为规整、部分区域内存在细长裂纹;高温下和高温后受压破坏的大理岩细观结构差异较大;800℃之前大理岩总体的质量百分比没有明显变化,温度达到800℃时大理岩各元素的质量百分比发生较大的变化,Ca元素的质量百分比急剧下降而Si元素的质量百分比迅速上升,说明其结构可能发生由晶态向非晶态的相转变,致使大理岩的力学指标骤降。Exploring the effect mechanism of high temperature on rock,which will has important significance for solving the problems of high temperature rock engineering.The measurement of surface element distribution,the surface morphology and mesostructural analysis have been tested for Xuzhou marbles that failed under uniaxial compression at different temperatures（20 ℃,200 ℃,400 ℃,600 ℃,800 ℃ andexperienced 400 ℃,600 ℃ and 800 ℃） using S–3000 N scanning electron microscopy made by Japan＇s Hitachi Ltd.A rational explanation in the mesoscopic level has been given on the characteristics of deformation,strength and failure of marble which experienced different temperatures.The test results show that the particles of Xuzhou marble are relatively thick,typical cleavage crack,cracks in part particle or between the particles at 20 ℃,while there are apparent fragmentations on the port surface,the particles become smaller,forms are more structured,and slender cracks exist in some areas at 800 ℃;The mesostructure of marbles that failed under uniaxial compression is quite different at high temperature and after high temperature.Generally the atomic percentage of marble doesn t change significantly before 800 ℃;When temperature reaches 800 ℃,the weight percentage of elements of marble takes place more change.The weight percentage of Ca declines sharply and that of Si raises rapidly which indicate that the structure of marble perhaps occurs phase transition from crystalline to amorphous and results in the plummeting of the mechanical index of marble at 800 ℃.

关 键 词：岩石力学 高温 大理岩 受压破坏 细观结构 试验 

分 类 号：TU45[建筑科学—岩土工程]