Dynamics of Water-Rock Interaction in Rock Scour

流水冲刷岩石是景观演变中的一个重要现象，也是世界上许多水坝面临的一个关键问题。在许多水坝遗址和多山的小溪河道中进行的实地观察表明，只要水流速度足够快，相对较小的水量就能从河道中带走令人惊讶的大块岩石。就大坝溢洪道而言，最近发生的几起事件造成了侵蚀，威胁到大坝本身的实际稳定和安全，并导致代价高昂的紧急行动。这项研究是一项跨学科的努力，旨在对这一过程有更好的物理理解。水槽的实验室实验和实地观察将用于建立一个数学模型，以评估和预测这一过程的严重程度。最终目标是通过预测需要加强的关键区域来提高现有水坝的安全性，以防止冲刷的发展。鉴于由于气候变化而观测到的极端天气模式日益增多，这一努力尤为重要。该奖项的更广泛影响将是对河流侵蚀导致的景观演变的新认识，提高对水坝因潜在的漫灌和灾难性洪水而面临的风险的认识，以及在本科和研究生地球科学与工程教育中引入新的概念。目前的冲刷预测模型仅限于非常简单的二维岩石不连续面几何和结构的表示，并且没有充分考虑节理方向对岩石块体可移除性的影响。此外，这些方法并没有考虑到单纯滑动或隆起以外的水动力对块体侵蚀/移除的潜在运动学影响。这项研究是一个综合的实验室和实地研究计划，以获得高分辨率的实地数据，包括速度和动态水压测量，从现场原型和比例模型水力实验室测试。目的是利用实验和现场数据更好地了解块状岩体的冲刷力学，并开发能够捕捉流体-块状岩石相互作用动力学的适当分析工具。

Scour of rock by running water is an important phenomenon in landscape evolution and it has been identified as a critical issue facing many of the world's dams. Field observations at numerous dam sites and in mountainous creek channels show that surprisingly large blocks of rock can be plucked from the stream channels by relatively small volume of water as long as it flows at sufficiently high velocity. In the case of dam spillways, several recent events have produced erosion that threatened the actual stability and safety of the dams themselves and resulted in very costly emergency actions. This research is an interdisciplinary effort aimed at developing a better physical understanding of the process. Laboratory experiments in a flume and field observations will be used to create a mathematical model for the evaluation and prediction of the severity of the process. The ultimate goal is to enhance the safety of existing dams by being able to predict the critical zones which need to be strengthened in order to prevent scour from developing. This effort is particularly important in view of the increasing extreme weather patterns being observed as a consequence of climate change. The broader impacts of the award will be a new understanding of landscape evolution by stream erosion, an improved understanding of the risks to dams as a result of potential overtopping and catastrophic flooding, and the introduction of new concepts in undergraduate and graduate earth science and engineering education.Current scour prediction models are limited to very-simple representation of the geometry and structure of the rock discontinuities in 2D, and do not adequately account for the effect of joint orientation on the removability of rock blocks. Furthermore, these approaches do not account for the potential for the kinematics of the block erosion/removal due to hydrodynamic forces beyond simple sliding or uplift. This research is an integrated program of laboratory and field studies to obtain high resolution field data, including velocity and dynamic water pressure measurements, from field prototype and scaled model hydraulic laboratory tests. The objective is to use the experimental and field data to develop a better understanding of the mechanics of scour of blocky rock masses and to develop appropriate analytical tools capable of capturing the dynamics of fluid-blocky rock interaction.