CAREER: Micromechanical Model of Undrained Cyclic Soil Behavior

职业：不排水循环土壤行为的微力学模型

• 批准号: 9875334
• 负责人: Thomas Price
• 金额: $ 21万
• 依托单位: Mississippi State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-15 至 2001-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9875334&HistoricalAwards=false
• 关键词: CAREER; Micromechanical; Model; Undrained; Cyclic

9875334 Thomas E. Price Mississippi State University CAREER: Micromechanical model of undrained cyclic soil behavior Abstract The objective of this study is to extend existing Discrete Element Modeling (DEM) technologies to explicitly account for pore fluid response in saturated soils. DEM methodologies act through consideration of the forces acting on individual soil particles within the soil mass, and are particularly well suited to problems in which large particle deformations are expected to occur. The rapid growth in recent years of computing power has popularized the use of DEM in calculating the behavior of granular soils. However, it has proven difficult to explicitly account for the response of the continuum pore fluid in computing the response of the soil mass. In this study, a three-dimensional numerical, micromechanical model of fluid-saturated cohesionless soil will be developed. The soil-phase discrete element model will interface with a finite element representation of the fluid continuum. The fluid model has been developed from the well-known equations of motion for two-phase porous media. The resulting model will enable extensive numerical testing of soil samples, including soils for which insufficient empirical data is available to calibrate continuum models. Because of the micromechanical nature of DEM, the data obtained will be of significantly higher resolution than is possible through laboratory or field studies. The numerical model thus developed will provide a powerful tool to augment the existing database of analytic and empirical soil response data. Potential application areas include fines migration beneath pavement slabs, earthquake-induced liquefaction, and environmental transport phenomena. Student participation throughout the course of the study will be enacted at both the graduate and senior undergraduate level. Students not directly involved in the study will benefit by means of a course module on DEM to be added to the curriculum of a graduate computational mechanics course. Meaningful partnering with the Pavements and Airfields Division of the Corps of Engineers Geotechnical Laboratory will ensure applicability of the study findings. Finally, dissemination of the study results to more distant researchers will be achieved through publishing of the study results, through both conventional

托马斯E.密西西比州立大学职业生涯：不排水循环土壤行为的微观力学模型 摘要 本研究的目的是扩展现有的离散元模型（DEM）技术，明确占孔隙流体在饱和土壤中的反应。 DEM方法通过考虑作用在土体内单个土颗粒上的力来起作用，并且特别适合于预计会发生大颗粒变形的问题。 近年来计算能力的迅速增长使离散元法在计算粒状土特性中的应用得到推广。 然而，它已被证明是很难明确的连续孔隙流体的响应计算中的响应的土体。 本研究将建立一个流体饱和无粘性土的三维数值细观力学模型。土壤相离散元模型将与流体连续体的有限元表示接口。 流体模型是从众所周知的两相多孔介质运动方程发展而来的。由此产生的模型将使广泛的土壤样品，包括土壤的经验数据不足，可用于校准连续模型的数值测试。由于DEM的微观力学性质，所获得的数据的分辨率将比通过实验室或现场研究获得的分辨率高得多。因此，开发的数值模型将提供一个强大的工具，以增加现有的数据库的分析和经验土壤响应数据。 潜在的应用领域包括路面板下的细粒迁移、地震引起的液化和环境运输现象。 整个研究过程中的学生参与将在研究生和高年级本科生水平制定。 不直接参与研究的学生将受益于DEM的课程模块被添加到研究生计算力学课程的课程。与工程兵岩土实验室的路面和机场部门的有意义的合作将确保研究结果的适用性。最后，将通过发表研究结果，通过传统的