Collaborative Research: Resilience of Geotechnical Infrastructure under a Changing Climate: Quantitative Assessment for Extreme Events

合作研究：气候变化下岩土基础设施的复原力：极端事件的定量评估

• 批准号: 1634748
• 负责人: Farshid Vahedifard
• 金额: $ 21.26万
• 依托单位: Mississippi State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2020-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1634748&HistoricalAwards=false
• 关键词: Collaborative; Research; Resilience; Geotechnical; Infrastructure

This award funds a collaborative and interdisciplinary research project focused on quantitatively assessing the performance of critical geotechnical infrastructure (i.e., natural and engineered earth structures) to climatic extremes and natural hazards under current and changing climate. While several large-scale studies have been conducted to evaluate implications of climate change, there is a clear gap in the state of our knowledge on regional- and structural-scale performance assessment of geotechnical infrastructure under myriad manifestations of global change. In this project, we focus on multiple hazards including increased intensity of extreme precipitation events, sea-level rise, and temperature extremes. The outcome of this research is expected to enhance our understanding about the resilience and reliability of our infrastructure under recent climate trends. In addition, this research will enhance the current analysis of existing geotechnical infrastructure, as well as the design and implementation of future geotechnical infrastructure by assessing the risks associated with a changing climate. In connection with this project, a number of educational and outreach efforts (including new learning tools) will be integrated into undergraduate and graduate courses taught by the investigators. This project will also provide the opportunity of project-based learning for students interested in pursuing science and engineering careers.This award will provide a quantitative assessment of the resilience of geotechnical infrastructure to extreme events under a changing climate. The project will address the following research questions: (I) How does the rate and variability of a changing climate affect recurrence intervals of climatic extremes and natural hazards (2) How does soil behavior vary under thermo-hydro-mechanical (THM) processes imposed by climate-adjusted extremes (3) How do climate extremes and natural hazards affect the short-term and long-term behavior of geotechnical structures. To properly address these questions, we will quantify the impact of climate change on both factors governing regional and structural responses to extremes: supplies (e.g., shear strength and compressibility of soil) and demands (e.g., loadings imposed to the structure due to climate extremes and natural hazards) through three main Tasks. Task 1 will extend the Non-stationary Extreme Value Analysis (NEVA) to obtain recurrence intervals of extremes under climate change. Employing NEVA will address one of the main shortcomings in similar studies that ignore the non-stationary nature of extremes in a warming climate. Task 2 will include using NEVA outputs to assess the impacts of climate extremes on the shear strength and compressibility of soil under multi-physics processes. In Task 3, the results from the first two tasks will be integrated in a set of numerical and analytical models to simulate short-term and long-term behaviors of geotechnical structures. The working hypothesis is that variations in temperature and soil moisture in variably saturated soil will govern the mechanical behavior and soil-structure interaction in geotechnical infrastructure. The research goal is to understand the impacts of extreme events under a changing climate on geotechnical infrastructure, and incorporate these impacts into the engineering analysis of existing geotechnical infrastructure as well as the design of future geotechnical infrastructure. In pursuit of this goal, the research objectives of this project are to: 1) Characterize the compressibility and shear strength of soil under non-isothermal conditions, and 2) Evaluate the impacts of climate extremes and natural hazards on the behavior of critical geotechnical structures using coupled THM numerical and analytical models.

该奖项为一个合作和跨学科研究项目提供了旨在定量评估关键岩土基础设施（即自然和工程地球结构）的绩效，以在当前和气候变化下的气候极端和自然风险。 尽管已经进行了几项大规模研究来评估气候变化的影响，但在全球变化的无数表现下，我们对岩土技术基础设施的区域和结构规模绩效评估的知识状况存在明显的差距。 在这个项目中，我们关注多种危害，包括增加极端降水事件的强度，海平面上升和极端温度。 这项研究的结果有望增强我们对最近气候趋势下基础设施的弹性和可靠性的理解。 此外，这项研究将通过评估与气候变化相关的风险来增强现有岩土基础设施的当前分析，以及未来岩土基础设施的设计和实施。与该项目有关，许多教育和推广工作（包括新的学习工具）将纳入调查人员教授的本科和研究生课程中。该项目还将为有兴趣从事科学和工程职业的学生提供基于项目的学习的机会。该奖项将对在不断变化的气候下对极端事件的岩土技术基础设施的弹性进行定量评估。 该项目将解决以下研究问题：（i）气候变化的速度和变化如何影响气候极端和自然危害的复发间隔（2）在热 - 氢化机械（THM）过程中，土壤行为在气候调整后极端施加的过程中如何变化（3）气候极端和自然危害如何影响短期和长期的构建范围。为了正确解决这些问题，我们将量化气候变化对极端区域和结构反应的因素的影响：供应（例如，土壤的剪切强度和可压缩性）和需求（例如，由于气候极端和自然危害而施加的负载，施加在结构上，施加了三个主要任务）。 任务1将扩展非平稳的极值分析（NEVA），以获得气候变化下极端的复发区间。 采用NEVA将解决类似研究的主要缺点之一，这些研究忽略了温暖气候下极端的非平稳性质。 任务2将包括使用NEVA输出来评估气候极端对多物理过程中土壤剪切强度和可压缩性的影响。 在任务3中，前两个任务的结果将集成到一组数值和分析模型中，以模拟岩土技术结构的短期和长期行为。 工作假设是，饱和土壤中温度和土壤水分的变化将控制岩土基础设施中的机械行为和土壤结构相互作用。 研究目标是了解气候不断变化的极端事件对岩土基础设施的影响，并将这些影响纳入现有岩土技术基础设施的工程分析以及未来岩土技术基础设施的设计。 为了实现这一目标，该项目的研究目标是：1）表征在非等温条件下土壤的可压缩性和剪切强度，以及2）评估气候极端和自然危害对关键岩土技术结构的行为的影响。

项目成果

Geotechnical Engineering in the Face of Climate Change: Role of Multi-Physics Processes in Partially Saturated Soils

面对气候变化的岩土工程：多物理过程在部分饱和土壤中的作用

• DOI: 10.1061/9780784481585.035
• 发表时间: 2018
• 期刊: Geotechnical Special Publication No. 295
• 作者: Vahedifard, Farshid;Williams, James M.;AghaKouchak, Amir
• 通讯作者: AghaKouchak, Amir

Toward A Hierarchal Framework for Modeling Cascading Effects of Drought-Precipitation on Earthen Structures

建立模拟干旱降水对土体结构的级联效应的层次框架

• 发表时间: 2019
• 期刊: ICONHIC2019
• 作者: Mortezaei, K.

Effects of Climate Change on Fragility Curves of Earthen Levees Subjected to Extreme Precipitations

气候变化对极端降水条件下土堤脆弱性曲线的影响

• DOI: 10.1061/9780784480724.045
• 发表时间: 2017
• 期刊: Geotechnical Special Publication No. 285
• 作者: Jasim, Firas H.;Vahedifard, Farshid;Ragno, Elisa;AghaKouchak, Amir;Ellithy, Ghada
• 通讯作者: Ellithy, Ghada

Stability analysis of unsaturated slopes under elevated temperatures

• DOI: 10.1016/j.enggeo.2021.106317
• 发表时间: 2021-08
• 期刊: Engineering Geology
• 影响因子: 7.4
• 作者: Sannith Kumar Thota;F. Vahedifard

Temperature-Dependent Model for Small-Strain Shear Modulus of Unsaturated Soils

非饱和土小应变剪切模量的温度相关模型

• DOI: 10.1061/(asce)gt.1943-5606.0002406
• 发表时间: 2020
• 期刊: Journal of Geotechnical and Geoenvironmental Engineering
• 影响因子: 3.9
• 作者: Vahedifard, Farshid;Thota, Sannith Kumar;Cao, Toan Duc;Samarakoon, Radhavi Abeysiridara;McCartney, John S.
• 通讯作者: McCartney, John S.