Collaborative Research: Multi-Block System Response to Hydraulic Loads in Rock Scour

水力冲刷是景观演变的基本过程，在这种过程中，流动的水从破碎的岩体中侵蚀出大的、有能力的岩石块。这一过程还影响到与水相互作用的工程结构，如水坝和桥梁，并往往导致运营和安全问题，因为大量材料的侵蚀可能会损害结构基础和可使用性。本研究使用联合水槽和数值模拟，以建立一个更全面的了解水力拔出的力学，这将通知基础设施的设计和修复。这种机械的理解的管理模式的故障将有可能确定最有效的设计或补救策略，也可以纳入景观演变模型。采摘的多尺度和渐进性探索的系统手段将提供洞察力的关键参数，应考虑在实时危害分析和景观演变。此外，作为这项研究的一部分开发的软件将开源发布，以供研究人员和工程师使用。实验数据集也将存储在一个公共存储库中，以便更广泛地使用和访问。准确预测拔出的可能性需要了解断裂岩体或工程材料的不同特性如何与流过、绕过和穿过它的流体的流动特性相互作用。目前还不完全了解这些特性的变化如何影响拔出，在目前的冲刷评估方法中也没有考虑到这一点，尽管潜在的叠加效应可以降低冲刷的阈值。这项研究将开发评估不同材料和流动特性之间相互作用的能力，以便更全面地了解采摘过程。这将通过一个配对的实验和数值方法，应用缩放水槽实验和耦合离散元和格子玻尔兹曼方法数值模拟来实现。这些能力将使冲刷评估方法，通过限制数量和程度的简化假设，需要在基于物理的模型，远离物理学。从这项研究中获得的基本力学的理解和多块流体系统的最关键特征的识别将为应用于工程结构的稳定性和修复的进一步研究提供信息，该奖项反映了美国国家科学基金会的法定使命，并被认为是值得支持的，通过评估使用基金会的智力价值，更广泛的影响审查标准。

Scour by hydraulic plucking is a fundamental process in landscape evolution where large, competent rock blocks are eroded from a fractured rock mass by flowing water. This process also affects engineered structures interacting with water, such as dams and bridges, and often leads to operational and safety concerns since erosion of large volumes of material can compromise structure foundations and serviceability. This research uses joint flume and numerical modeling to establish a more comprehensive understanding of the mechanics of hydraulic plucking, which will inform infrastructure design and remediation. This mechanistic understanding of the governing modes of failure will make it possible to identify the most efficient design or remediation strategy, and can also be incorporated into landscape evolution models. The systematic means by which the multi-scale and progressive nature of plucking is explored will provide insights into key parameters that should be considered in real-time hazard analysis and landscape evolution. Additionally, software developed as part of this research will be released open-source to make it available to researchers and engineers. The experimental data set will also be stored in a public repository to be more broadly available and accessible.Accurately predicting the likelihood of plucking requires an understanding of how different properties of the fractured rock mass or engineered material interplay with flow characteristics of the fluid flowing over, around, and through it. It is not fully understood how variation in these properties influence plucking, nor is it considered in present scour evaluation methods, even though the potential stacking of effects could lower the threshold for scour. This research will develop capabilities that assess the interaction between different material and flow properties in order to develop a more comprehensive understanding of the plucking process. This will be achieved through a paired experimental and numerical approach that applies scaled flume experiments and coupled Discrete Element and Lattice Boltzmann Method numerical simulations. These capabilities will enable scour assessment methods that move away from empiricism by limiting the number and extent of simplifying assumptions that need to be made in physics-based models. The understanding of the underlying mechanics gained from this research and identification of the most critical features of the multi block-fluid system will inform further research applied to stability and remediation of engineered structures, as well as descriptions of rates of bedrock erosion in natural channels.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.