Integrated Framework for 3D Analysis of Soil-Pile Interaction

这笔赠款为土桩相互作用问题的理论和实验研究提供资金。基于对桩周围位移场的数学形式、变分法和能量原理的深入了解，将开发用于分析承受组合载荷的桩的框架的基本原理。 将对安装在半圆形室内的半截面仪器模型桩进行一系列荷载试验，半圆形室内沿直径沿着有有机玻璃边界。采用数字图像相关技术（DIC）研究模型桩在安装和加载阶段周围土体的位移场。模型桩-土界面行为将通过图像分析和常规传感器捕获。 这些实验将提供数据，将是有用的，在建立的一般数学形式的受载桩周围的位移场。 一般的理论框架的验证将通过与一些负载测试的结果进行比较，对仪器模型pile.The拟议的工作将有助于弥合知识差距，目前存在的理解土桩相互作用过程。三维土-桩相互作用分析的框架和实验结果将为解释土壤分层和土壤特性空间异质性对桩阻力的影响奠定基础，这将使未来的理论发展能够使工程师快速分析目前只能用非常昂贵和耗时的三维有限元分析的问题。能够考虑到地面空间变异性的分析的可用性将有助于各种应用，包括评估改造现有结构的必要性和地面工程干预措施减轻地震风险的有效性。 这将是特别有用的，因为美国正在改造和建设新的基础设施，这需要评估现有的和新的桩基设计。

This grant provides funding for a theoretical and experimental study of soil-pile interaction problems. The fundamentals of a framework for the analysis of piles subjected to combined loading, based on insights into the mathematical form of the displacement field around the pile, calculus of variations and energy principles, will be developed. A series of load tests will be performed on half-section instrumented model piles installed in a half- circular chamber containing a plexiglass boundary along its diameter. The displacement field in the soil around model piles will be studied during the installation and loading stages using the Digital Image Correlation (DIC)technique. The model pile-soil interface behavior will be captured by both image analysis and conventional sensors. These experiments will provide data that will be useful in the establishment of the general mathematical form of the displacement field around loaded piles. Validation of the general theoretical framework will be done by comparison with results of a number of load tests on instrumented model piles.The proposed work will help bridge knowledge gaps that currently exist in the understanding of the soil-pile interaction process. The framework for 3D soil-pile interaction analysis and the results of the experiments will establish the basis for accounting for the effects of soil layering and spatial heterogeneity of soil properties on pile resistance, which will allow future development of theories that will enable engineers to quickly analyze problems that at present can only be analyzed with very costly and time-intensive 3D FEA. The availability of an analysis that can take into account spatial variability in the ground will be useful in a variety of applications, including the assessment of the need to retrofit existing structures and the effectiveness of ground engineering interventions to mitigate seismic risks. This will be particularly useful as the United States works on retrofitting and building new infrastructure, which requires both the assessment of existing and design of new pile foundations.