岩土材料中冰分布状态的冷冻电镜表征方法  

Characterization of Ice Distribution in Geotechnical Materials Based on Cryo-electron Microscopy

作　　者：王子振[1,2] 王晓康 申凯翔[3] 苏捷 赵志强 周卫东 WANG Zizhen;WANG Xiaokang;SHEN Kaixiang;SU Jie;ZHAO Zhiqiang;ZHOU Weidong(College of Petroleum Engineering,China University of Petroleum(East China),Qingdao 266580,Shandong,China;Key Laboratory of Unconventional Oil&Gas Development of Ministry of Education,China University of Petroleum(East China),Qingdao 266580,Shandong,China;Guangzhou Marine Geological Survey,Guangzhou 510075,China;School of Chemistry and Chemical Engineering,Shandong University,Jinan 250100,China;Institute of Geological Measurement and Control Technology,Sinopec Jingwei Co.Ltd.,Qingdao 266000,Shandong,China)

机构地区：[1]中国石油大学(华东)石油工程学院,山东青岛266580 [2]中国石油大学(华东)非常规油气开发教育部重点实验室,山东青岛266580 [3]广州海洋地质调查局,广州510075 [4]山东大学化学与化工学院,济南250100 [5]中石化经纬有限公司地质测控技术研究院,山东青岛266000

出　　处：《实验室研究与探索》2024年第2期8-12,114,共6页Research and Exploration In Laboratory

基　　金：国家自然科学基金项目(52074328)。

摘　　要：为从微观角度定量描述冰在岩土材料中的分布特征,基于冷冻电镜技术提出了一种微观尺度的实验表征方法。针对不同冰饱和度人造岩芯样品的二次电子图像和能谱分析图,通过元素含量分布、升华前后图像对比确认了冰在岩土材料中的分布状态。随着冰饱和度的增加,骨架孔隙被冰填充、骨架颗粒表面被冰包裹区域增大,样品断面更密实平整,岩土骨架的堆积结构特征变弱。在背散射电子图像中,冰的图像比岩土骨架亮度低、灰度高,基于此构建了冰饱和度的数字图像计算方法。该方法计算的升华前冰饱和度与样品预制冰饱和度偏差小于5%,验证了其可靠性。Quantitatively describing the distribution characteristics of ice in geotechnical materials from a microscopic perspective is crucial.Based on the technique of cryo-electron microscopy(Cryo-EM),an experimental characterization method of the distribution of ice in porous geotechnical materials is proposed.For artificial core samples with different ice saturations,the distribution of ice in porous geotechnical materials is confirmed by elemental content distribution and comparison of images before and after sublimation based on the secondary electron(SE)images and energy spectrum analysis maps of the samples at different magnifications.With the increase of ice saturation,the pore space of the skeleton is filled by ice,the area of the skeleton particle surface wrapped by ice increases,the sample section is denser and flatter,and the stacking structural characteristics of the geotechnical skeleton become weaker.In the backscattered electron(BSE)image,the image of ice is less bright than that of the geotechnical skeleton,based on which a digital image calculation method for the ice saturation of the sample is developed.The deviation of the ice saturation calculated by this method before sublimation from the ice saturation of the predesigned sample is less than 5%,and the results are accurate and reliable.

关 键 词：岩土材料 冷冻电镜 冰分布状态 数字图像分析 

分 类 号：TU445[建筑科学—岩土工程]