Strain Distribution Within Geosynthetic Reinforced Soil Slopes

土工合成材料加筋土坡内的应变分布

• 批准号: 0401494
• 负责人: Jorge Zornberg
• 金额: $ 12.55万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2006-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0401494&HistoricalAwards=false
• 关键词: Strain; Distribution; Within; Geosynthetic; Reinforced

Soil reinforcement using geosynthetics is a very attractive alternative for highway embankment and retaining wall projects because of the economic benefits it offers in relation to cenventional retaining structures. Desigh of reinforced soil slopes is typically performed using software-based techniques (limit equilibrium), which require significant assumptions regarding the distribution of strains within the reinforcement elements. However, to date, the assumed strain distributions have not been fully validated against monitored results. One consequence of this is a perceived overconservatism in design.The overall objective of this research initiative is to generate and integrate (via centrifuge modeling, digital image analysis, and finite element analysis) data that will provide a definite answer regarding the strain distribution to be adopted in reinforced soil slope design. Specificaly, this project will integrate results from the following five phases: (i) a centrifuge modeling investigation undertaken to generate experimental data on the performance fo geosynthetic reinforced soil slopes under working stress conditions; (ii) a digital image processing and analysis effort performed to collect and evaluate strain information from inflight-captured images of videotaped centrifuge models; (iii) a numerical (finite element) study performed to compile parametric evaluations of reinforced soil slope behavior, after having calibrated numerical procedures against data collected in the previous experimental phase; (iv) an evaluation effort to incorporate findings on reinforcement strain distribution into current reinforced soil guidelines; and (v) an educational component to integrate digital video clips of centrifuge geotechnical models into multimedia presentations to be used for undergraduate and graduate geotechnical instructions as well as for recruitment of underrepresented minority high school students into engineering programs.In addition to the specific goal of refining design guidelines for geosynthetic reinforced soil slopes by gaining better understanding of the pattern of strain distributions, the proposed research is the cornerstone of larger, ongoing agendas under active development on reinforced soil research by the PI and on geotechnical modeling at the PI's institution. In fact, the proposed investigation will initiate implementation of innovative procedures invilving digital image analysis in geotechnical centrifuge testing at the University of Colorado, will contribute to ongoing efforts of cross-validation between physical and numerical modeling of geotechnical systems, and will foster integration of research into engineering education.

使用土工合成材料加固土壤对于公路路堤和挡土墙项目来说是一种非常有吸引力的替代方案，因为它比传统的挡土结构具有更高的经济效益。 加筋土坡的设计通常使用基于软件的技术（极限平衡）进行，这需要对加筋元件内应变的分布进行重要假设。 然而，迄今为止，假设的应变分布尚未根据监测结果得到充分验证。 这样做的后果之一是设计中被认为过于保守。这项研究计划的总体目标是生成和集成（通过离心机建模、数字图像分析和有限元分析）数据，这些数据将提供有关应变分布的明确答案加筋土边坡设计中采用。 具体来说，该项目将整合以下五个阶段的结果：（i）进行离心机建模研究，以生成土工合成材料加筋土斜坡在工作应力条件下性能的实验数据； (ii) 进行数字图像处理和分析工作，以从飞行中拍摄的离心机模型录像图像中收集和评估应变信息； (iii) 在根据前一实验阶段收集的数据校准数值程序后，进行数值（有限元）研究，以编制加筋土边坡行为的参数评估； (iv) 一项评估工作，将加固应变分布的发现纳入当前的加固土壤指南中； (v) 教育部分，将离心机岩土工程模型的数字视频剪辑整合到多媒体演示中，用于本科生和研究生岩土工程教学，以及招募代表性不足的少数族裔高中生参加工程项目。通过更好地了解应变分布模式，完善土工合成材料加筋土边坡的设计指南，拟议的研究是 PI 和PI 机构的岩土建模。 事实上，拟议的调查将在科罗拉多大学启动岩土工程离心机测试中涉及数字图像分析的创新程序的实施，将有助于岩土工程系统物理和数值建模之间正在进行的交叉验证工作，并将促进研究的整合进入工程教育。