CRII: III: RUI: Multiphysics Modeling of Slope Stability in Post-Wildfire Environment

CRII：III：RUI：野火后环境中边坡稳定性的多物理场建模

• 批准号: 2153370
• 负责人: Yifei Ma
• 金额: $ 17.49万
• 依托单位: Lawrence Technological University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2153370&HistoricalAwards=false
• 关键词: CRII; III; RUI; Multiphysics; Modeling

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).Post-wildfire landslides and debris flows in recent years in the Western U.S. have become more frequent and led to numerous fatalities and large economic costs. The increase in landslide susceptibility in post-wildfire environment has been attributed to the increases in soil moisture and reduction of covering vegetation and root anchoring effect. The post-wildfire hillslope stabilization and rehabilitation methods are strongly relying on the knowledge of the engineering behaviors of the wildfire-burnt soil and the effect of post-wildfire environmental factors (e.g., heating-cooling and wetting-drying cycles). However, the transitioning mechanisms from increasing soil movement to catastrophic landslide, along with the engineering characteristics of wildfire-burnt soil, remain unexplored. There is currently no readily available approach or framework to evaluate the wildfire-burnt slope stability or soil properties. This project seeks to serve the national interest by developing a multiphysics and multiscale numerical framework to analyze the engineering properties of wildfire-burnt soil under extreme conditions during and after a wildfire, thus informing our strategies for slope stabilization and remediation. Expected project’s outcomes, such as the physics-based models, multiphysics coupling algorithms, and decision-supporting numerical data, will promote the fundamental understanding of the multiphase granular flow and renovate the technology in wildfire-burnt slope stabilization. This project will also provide a multidisciplinary learning platform through project-based challenging activities to leverage a greater awareness amongst the engineering students about the effectiveness of numerical modeling in addressing engineering challenges related to sustainable and energy viable society.The main objective of this project is to quantify the fundamental physics that govern the mechanical and hydrologic soil behaviors and therefore slope stability in post-wildfire environments. The approach to achieve the initiative will combine analysis and numerical simulations. Towards this end, the research team will (1) empirically identify the wildfire impacts on soil erosion, including reduction of root anchoring effect and subsurface seepage flow; (2) analytically evaluate the fundamental physics during and after the wildfire, including the effect of severe temperature gradient and wetting-drying cycles on the soil fabric; and (3) numerically model the macro-scale slope stability under various combinations of micro-parameters and environmental conditions. The stability of wildfire-burnt slopes will, for the first time, be evaluated through physics-based correlations that are informed by the particle-scale measurements from the numerical models. The project puts forward an innovative cross-disciplinary multiphysics research that will advance our fundamental understanding of multi-phase wildfire-burnt debris flow and promote insights into the correlations between micro-scale physicochemical forces and macro-scale mechanical wildfire-burnt soil behaviors. The combination of empirical, analytical, and numerical analyses provides a powerful range of interdisciplinary tools for understanding the effect of coupled physical-thermal-mechanical-hydrologic process on the soil engineering properties.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.

该奖项是根据2021年《美国救援计划法》的全部或部分资助（公法117-2）。近年来，野外火山滑坡和碎屑流动越来越频繁，导致了许多死亡和巨大的经济成本，导致了势力范围内的水地易变，从而增加了土地上的覆盖范围，并增加了土壤的生效，并弥补了土壤的范围。山坡稳定和康复方法强烈依赖于野火燃烧土壤的工程行为的知识以及后野火后环境因素的影响（例如，加热冷却和润湿干燥周期）。然而，从增加土壤运动到灾难性的滑坡的过渡机制以及野火燃烧土壤的工程特征仍然是出乎意料的。目前尚无容易获得的方法或框架来评估野火弯曲的斜坡稳定性或土壤特性。该项目旨在通过开发多物理学和多尺度数值框架来为国家利益提供服务，以在野火期间和之后分析野火燃烧土壤的工程特性，从而为我们的坡度稳定和修复策略提供了信息。预期项目的结果，例如基于物理的模型，多物理耦合算法以及决策支持的数值数据，将促进对多相颗粒流量和翻新野火弯曲斜率稳定的基本理解。该项目还将通过基于项目的挑战活动提供一个多学科学习平台，以利用工程专业的学生对数值建模在应对与可持续和能源可行社会相关的工程挑战方面的有效性。该项目的主要目标是量化该项目的基本物理学，从而管理机械和水文的土壤行为和水平行为稳定性，从而在slopection in slopection in Post slopfire in Post forefire。实现该计划的方法将结合分析和数值模拟。为此，研究团队将（1）从经验上确定野火对土壤侵蚀的影响，包括减少根锚定效应和地下渗流流量； （2）在野火期间和之后分析评估基本物理，包括严重温度梯度和润湿干燥周期对土壤织物的影响； （3）在微观参数和环境条件的各种组合下，在数值上对宏观斜率稳定性进行建模。野火燃烧插槽的稳定性将首次通过基于物理的相关性来评估，这些相关性通过数值模型的粒子尺度测量结果告知。该项目提出了一项创新的跨学科多物理学研究，该研究将促进我们对多相野火燃烧碎片流的基本理解，并促进对微观物理力与宏观机械尺度机械野火燃烧土壤行为之间相关性的见解。经验，分析和数值分析的结合提供了一系列强大的跨学科工具，用于理解耦合的物理和机械力学流行过程对土壤工程特性的影响。该奖项反映了NSF的法规任务，并认为通过基金会的知识优点和更广泛的critia criperia criperia criperia criperia criperia criperia criperia criperia criperia the Issportion the the奖项。