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

该研究项目将重点推进对地震引发的边坡破坏机制的基本理解，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活跃地区造成了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，并且没有考虑到循环荷载下土壤行为的复杂性。本研究将建立一个有效的数值框架来分析整个破坏过程，从地面震动和破坏开始到破坏后的过程。该数值工具将适应大变形和水-机械耦合，并将与现有的基于连续体的本构模型兼容，用于模拟液化触发和循环迁移。开发的数值工具和教程手册将通过开源平台共享。这项研究还将辅以外联活动，包括为研究生举办讲座和为从业人员举办培训班。这项研究的结果可以提供一个更全面的了解与地震灾害有关的风险。本研究的目的是更好地捕捉和理解地震动特征、孔隙压力演化与边坡破坏最终迁移率之间的联系。因此，本项目的研究目标包括：(i)建立并验证一个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大变形的广义数值框架；（ii）量化失稳全过程孔隙水压力演化；（iii）将地面运动强度与破坏开始、破坏后行为和水力学响应联系起来。为了实现这些目标，现有的物质点法框架将进一步发展，以准确地模拟地面震动、现场响应和大变形。考虑材料阻尼和循环迁移率的现行本构模型将在同一框架内考虑，并对其性能进行评估。将利用离心机测试和现场案例研究的现有数据验证这些发展。该项目将使PI能够告知、推进和改变同震边坡稳定性分析的方法，特别是在复杂几何形状和关键基础设施处于危险中时。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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.