CAREER: Stress Redistribution Imaging for Rock Failure Prediction

职业：用于岩石破坏预测的应力重新分布成像

• 批准号: 0134034
• 负责人: Erik Westman
• 金额: $ 37.5万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0134034&HistoricalAwards=false
• 关键词: CAREER; Stress; Redistribution; Imaging; Rock

CMS-0134034PI: Erik WestmanInstitution: Virginia Polytechnic Institute and State UniversityTitle: "CAREER: Stress Redistribution Imaging for Rock Failure Prediction"This Faculty Early Career Development (CAREER) research and education project uses high-resolution, three-dimensional tomographic imaging to better understand and communicate the process of failure in rock. Accomplishing the ultimate goal of predicting rock mass failure will result in significantly reduced fatalities, lowered construction costs, and increased environmental protection. Failure prediction extends to all aspects of rock mechanics including tunnels, mines, rock slopes, earthquakes, waste repositories, and bridge and dam abutments. To predict rock failure, it is quite helpful to monitor the redistribution of stresses within the rock. Recent advances in computational power have allowed this to be done using acoustic waves and tomographic imaging. The basic principal behind monitoring the redistribution of stresses is that microfractures within the rock are closed under increased loading, allowing the acoustic wave to travel at a greater velocity and with less attenuation. This method has been used successfully in the laboratory and has had growing, but poorly founded, application in the field. This project will put the technique of imaging stress redistribution in rock on a sound theoretical and practical foundation by 1) standardizing methods and 2) extending results of prior studies into the gap between laboratory- and field-scale studies. Educational efforts related to rock failure prediction will also be enhanced.Specific tasks associated with both education and research include 1) generating three-dimensional tomographic images to observe relevant alterations to the fabric of rock samples loaded to failure, and 2) using those images to calibrate numerical modeling results. By collecting data as rock samples are loaded, time-lapse animations will be developed which will assist in the communication of stress-analysis to undergraduates. Additional educational efforts focus on transitioning from a presentational teaching method to a constructivist model for two of the proposer's undergraduate courses and developing a graduate-level course for understanding failure through coupled analysis of imaging and numerical modeling results.

CMS-0134034PI：Erik Westman机构：弗吉尼亚理工学院和州立大学标题：“职业：岩石破坏预测的应力重新分布成像”该教师早期职业发展（职业）研究和教育项目使用高分辨率、三维断层扫描成像来更好地理解并传达岩石的破坏过程。 实现预测岩体破坏的最终目标将显着减少死亡人数、降低建筑成本并加强环境保护。 失效预测扩展到岩石力学的各个方面，包括隧道、矿山、岩坡、地震、废物储存库以及桥梁和坝肩。 为了预测岩石破坏，监测岩石内应力的重新分布非常有帮助。 计算能力的最新进展使得这可以使用声波和断层扫描成像来完成。 监测应力重新分布的基本原理是，岩石内的微裂缝在增加的载荷下闭合，从而允许声波以更大的速度和更少的衰减传播。 该方法已在实验室中成功使用，并且在现场的应用也在不断增长，但基础较差。 该项目将通过 1) 标准化方法和 2) 将先前研究的结果扩展到实验室和现场规模研究之间的差距，为岩石中应力重新分布成像技术奠定坚实的理论和实践基础。 与岩石破坏预测相关的教育工作也将得到加强。与教育和研究相关的具体任务包括 1) 生成三维断层扫描图像以观察加载破坏的岩石样本结构的相关变化，以及 2) 使用这些图像校准数值模型结果。 通过在加载岩石样本时收集数据，将开发延时动画，这将有助于向本科生传达应力分析。 其他教育工作的重点是从提案者的两门本科课程的演示教学方法过渡到建构主义模型，并开发一门研究生课程，通过成像和数值建模结果的耦合分析来理解失败。