Unified Multi-phase Numerical Framework for Understanding Co-Seismic Slope Failures in Complex Sites

这项研究项目将致力于促进对地震引发的边坡破坏机理的基本了解，并将有助于预测、减少和减轻其破坏性后果。地震引发的边坡破坏在地震多发区造成重大的经济和生命损失。然而，解决同震边坡破坏的触发和跳动的最先进的程序是高度理想化的，并且没有包括在循环荷载作用下土壤行为的复杂性。这项研究将开发一个有效的数值框架来分析从地面震动和破坏开始到破坏后的整个破坏过程。该数值工具将适应大变形和流体-机械耦合，并将与现有的基于连续介质的本构模型兼容，用于模拟液化触发和循环迁移率。开发的数字工具和教程手册将通过开放源码平台共享。这项研究还将得到外联活动的补充，包括为研究生举办讲座和为从业人员举办培训课程。这项研究的成果可以更全面地了解与地震灾害相关的风险，目的是更好地捕捉和了解地面运动特征、孔压演化和最终边坡破坏活动之间的联系。因此，本项目的研究目标包括：(I)建立和验证一个通用的数值框架，能够在统一的计算框架内模拟地震荷载、场地反应和复杂场地的大变形；(Ii)量化整个失稳过程中的孔压演化；以及(Iii)将地面运动的强度与破坏开始、破坏后的行为和水力学反应联系起来。为了实现这些目标，现有的材质点方法框架将进一步发展，以准确地模拟地面震动、场地响应和大变形。考虑材料阻尼和循环迁移率的实用状态本构模型将在同一框架中考虑，并对其性能进行评估。将使用离心机测试和实地案例研究的现有数据来验证这些发展。该项目将允许PI告知、推进和改变处理同震边坡稳定性分析的方式，特别是对于复杂几何形状和关键基础设施处于风险中的情况。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This research project will focus on advancing the fundamental understanding of the mechanics of slope failures triggered by earthquakes and will help to predict, reduce, and mitigate their destructive consequences. Earthquake-triggered slope failures cause significant economic and life losses in seismically active regions. However, state-of-the-art procedures that address triggering and runout of co-seismic slope failures are highly idealized and do not incorporate the complexities of soil behavior subjected to cyclic loading. This research will develop a validated numerical framework to analyze the overall failure process, from the ground shaking and failure initiation to the post-failure processes. The numerical tool will accommodate large deformations and hydro-mechanical coupling and will be compatible with existing continuum-based constitutive models for the simulation of liquefaction triggering and cyclic mobility. The developed numerical tool and a tutorial manual will be shared through an open-source platform. The research will also be complemented by outreach activities, including lectures for graduate students and training sessions for practitioners. The outcomes of this research can be provide a more comprehensive understanding of the risk associated with earthquake hazards.The goal of this research is to better capture and understand the connection between ground motion characteristics, pore pressure evolution and final mobility of slope failures. Thus, the research objectives of this project include: (i) to establish and validate a generalized numerical framework capable of simulating earthquake loading, site response, and large deformations of complex sites, all within a unified computational framework; (ii) to quantify pore water pressure evolution during the entire instability process; and (iii) to correlate the intensity of the ground motions with the failure initiation, post-failure behavior, and hydro-mechanical response. To accomplish these objectives, the existing Material Point Method framework will be further developed to accurately simulate ground shaking, site response, and large deformations. State-of-practice constitutive models accounting for material damping and cyclic mobility will be considered in the same framework, and their performance will be evaluated. The developments will be validated using existing data from centrifuge testing and field case studies. This project will allow the PI to inform, advance, and transform the way co-seismic slope stability analyses are approached, especially for complex geometries and when critical infrastructure is at risk.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.