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

该研究项目将侧重于推进对地震引发的边坡破坏力学的基本理解，并将有助于预测，减少和减轻其破坏性后果。地震引发的边坡失稳在地震活跃区造成了重大的经济和生命损失。然而，国家的最先进的程序，解决触发和跳动的同震斜坡故障是高度理想化的，不包括土壤行为的复杂性，受到循环荷载。本研究将发展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力机械耦合，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流动性。将通过一个开放源码平台分享所开发的数字工具和一本教程手册。这项研究还将辅之以外联活动，包括为研究生举办讲座和为从业人员举办培训班。本研究的成果可以提供一个更全面的了解与地震灾害相关的风险，本研究的目的是更好地捕捉和理解地面运动特性，孔隙压力演变和最终的流动性的边坡故障之间的联系。因此，本计画的研究目标包括：（i）建立并验证一个能模拟复杂场地的地震荷载、场地反应及大变形的通用数值框架，所有这些都在一个统一的计算框架内;（ii）量化整个失稳过程中孔隙水压力的演化;以及（iii）将地面运动的强度与破坏开始、破坏后行为和水力机械响应相关联。为了实现这些目标，现有的材料点法框架将进一步发展，以准确地模拟地面震动，现场反应，和大变形。国家的实践本构模型占材料阻尼和循环流动性将被认为是在同一框架内，其性能将进行评估。将利用离心机测试和实地案例研究的现有数据对这些发展进行验证。该项目将使PI能够通知、推进和改变地震同震边坡稳定性分析的方法，特别是对于复杂的几何形状和关键基础设施处于风险中时。该奖项反映了NSF的法定使命，并被认为值得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来支持。

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.