Collaborative Research: Dynamic behavior of slickensided surfaces

合作研究：光滑表面的动态行为

• 批准号: 0324499
• 负责人: Ross Boulanger
• 金额: $ 6.57万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-03-01 至 2006-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0324499&HistoricalAwards=false
• 关键词: Collaborative; Research; Dynamic; behavior; slickensided

"Slickensides" are surfaces of weakness formed in stiff clays as a result of large shear displacements - on the order of 50 mm to 250 mm - concentrated on a discrete surface of sliding. Platy clay particles become aligned parallel to the surface of sliding, resulting in the formation of a smooth surface with shear strength that is much lower than the strength of the adjacent clay through which the slickensided surface forms.As a result of this low shear strength in comparison with the adjacent clay, slickensided rupture surfaces are likely loci of displacements during earthquakes. However, there have been no studies of the behavior of slickensided surfaces when subjected to the rapid cyclic loading that occurs during earthquakes. As a result, engineers must rely on assumption and judgment when estimating strengths for seismic deformation analyses, and these vary considerably among practicing engineers. For example, for one particular project in northern California, the difference of opinion regarding the shear strength that should be used resulted in recommendations for stabilization of the slopes that differed in cost by a factor of ten. At present, there is no way to determine whether one of these designs was dangerously inadequate, or the other was wasteful overkill.The broader impacts of this research program include opportunities for undergraduate and graduate students to participate in the laboratory experiments at Virginia Tech, and for freshman through senior-level students to observe the centrifuge experiments at UC Davis, and to work as assistants in preparing the centrifuge models. Both UC Davis and Virginia Tech have very active programs to recruit minority students to participate in research through the Minority Opportunities for Research in Engineering at UC Davis, and the Office of Minority Engineering Programs and coalition with Historically Black Colleges and Universities at Virginia Tech. The project also involves an active collaboration with Dr. Binod Tiwari of Niigata University, who has considerable experience in the types of experiments involved and will spend time at Virginia Tech and UC Davis, which will help to establish closer relationships between researchers in Japan and in the United States.

“滑动面”是由于大的剪切位移（约50 mm至250 mm）集中在离散的滑动面上而在硬粘土中形成的薄弱面。 片状粘土颗粒与滑动面平行排列，形成光滑面，其剪切强度远低于形成光滑面的相邻粘土的强度，由于与相邻粘土相比剪切强度较低，光滑面破裂面可能是地震时的位移点。 然而，还没有研究光滑表面在地震期间发生的快速循环荷载作用下的行为。 因此，工程师必须依赖于假设和判断时，估计强度的地震变形分析，这些有很大的差异，在实践中的工程师。 例如，对于北方加州的一个特定项目，关于应使用的抗剪强度的意见分歧导致了成本相差十倍的边坡稳定建议。 目前，还没有办法确定这些设计中的一个是危险的不足，还是另一个是浪费的过度。这项研究计划的更广泛的影响包括本科生和研究生有机会参加弗吉尼亚理工大学的实验室实验，大一到大四学生有机会观察加州大学戴维斯分校的离心机实验，并协助制作离心机模型。 加州大学戴维斯分校和弗吉尼亚理工大学都有非常活跃的项目，通过加州大学戴维斯分校的少数民族工程研究机会，以及少数民族工程项目办公室和弗吉尼亚理工大学历史上的黑人学院和大学联盟，招募少数民族学生参与研究。 该项目还涉及与新泻大学的Binod Tiwari博士的积极合作，他在所涉实验类型方面具有相当丰富的经验，并将在弗吉尼亚理工大学和加州大学戴维斯分校工作，这将有助于在日本和美国的研究人员之间建立更密切的关系。