首页土木建筑工程学院研究生导师论坛和专题讲座
标题 Big data-based statistical nanoindentation for extracting shale’s mechanical genes and beyond
主讲人 张国平
职称
职位
地点 力学楼二楼会议室
举办学院 土木建筑工程学院
举办时间 2018年6月12日15点正
主讲人简介 张国平博士就职于美国麻省大学(阿姆斯特), 是土木与环境工程系教授。于1991年取得清华大学水利工程和精密仪器双学士学位,于1994年取得清华大学岩土工程硕士学位,2002年获得美国麻省理工学院岩土工程博士学位及材料科学辅修学位。先后任职于中国建筑科学研究院(地基基础研究所),英国诺丁汉大学,美国路易斯安娜州立大学,和麻省大学。目前已发表论文100多篇,是美国土木工程师协会,黏土矿物协会,地球物理协会,美国石油工程师协会等其他协会会员。是英国Geotechnical Research 期刊编委,研究经费达9百多万美元,资助机构包括美国国家科学基金,中国自然科学基金,美国海洋气象局,HESS, SHELL, 中石油,晋煤集团,州交通部和其他企业和政府。
讲座简介 Shales represent one of the most complex composites found in the geosphere, and the safe and economical recovery of oil and gas from shale formations requires thorough understanding of their mechanical, geophysical, and hydraulic properties. This seminar presents the latest state-of-the-art nanomechanical technology for characterization of shales. Grid nanoindentation testing with Continuous Stiffness Measurement (CSM) method was employed to obtain massive data sets (i.e., big data) on the load-depth response of shales to indentation depths of up to 8000 nm. The depth-dependent data were then analyzed statistically at specified depths to extract the Young’s modulus and hardness at pertinent depths. A new data analytics method was then developed to process the data by considering the finite-sized indents and the surrounding effects, given that shales are multi-phase, multi-scale composites consisting of solid particles with sizes ranging from tens of nanometers to hundreds of micrometers as well as voids and organic. With the new data analytics, a series of physical and mechanical properties of shales was obtained, including: (1) the number of phases in the parent shale; (2) the volumetric fraction of each phase; (3) the mechanical properties (e.g., Young’s modulus and hardness) of each phase; and (4) the mechanical properties of the bulk shale as a composite. Moreover, data can also provide viable guidance for selecting appropriate indentation test parameters (e.g., indentation depth) for the determination of mechanical properties of certain individual phases (e.g., clay matrix, bulk shale). Moreover, future applications of this big data-based nanoindentation technique to other composite materials as well as shale softening and hydrofracturing are discussed.