Landslide risk evolution and the adequacy of risk evaluation criteria

加拿大的山体滑坡每年平均造成4人死亡，每年造成约2亿美元的损失。滑坡管理依赖于政府资源，通过安全系数、失败概率、风险排名或定量风险评估来评估风险等级。这些风险水平会随着时间的推移而变化，如果它们的可变性没有得到充分的理解和量化，边坡破坏及其负面后果的可能性就会增加。风险变异归因于对滑坡的认识水平、材料的逐步退化和外部因素（特别是天气）；然而，有限的研究解决了风险随时间变化背后的基本过程。我以前的工作重点是考虑到各种参数的不确定性，量化滑坡风险的框架的发展。这些框架是在目前关于风险可变性的知识状况下制定的，本质上是实用的。拟议的工作现在将推进滑坡风险随时间变化的基础研究，特别是考虑到气候变化，并评估滑坡风险可接受标准的充分性。据我所知，这项研究将在滑坡演化的物理学方面产生新的知识，这将为滑坡风险管理的实际方法的发展提供信息。第一个目标是了解两种不同类型滑坡地点的滑坡风险变化的基本过程：复合滑坡和易落岩滑坡。这项工作将开发一个框架，用于估计滑坡变形模式和外部因素变化的风险变化，特别是在气候变化的背景下，并开发复合滑坡的数值实现，以适应滑坡风险分析过程，以估计季节性和长期风险变化。第二个目标是在分析水库内的堑坡时量化模型不确定性的影响，并评估堑坡生命周期的不同阶段（设计，施工，运营，长期）评估标准的充分性。这项工作将通过遥感结合现场仪器来监测边坡，以促进开发评估不确定性减少的方法，并开发一种数值方法来估计长期边坡行为的变化，以评估在切割边坡生命的不同阶段最适当的边坡风险标准。该研究项目将培养两名博士生和一名研究助理，并将促进对滑坡风险季节性和长期变化的基本认识，特别是与气候变化有关的变化。这将为解决当前和未来滑坡风险的变化提供基础，以确保在公共和环境安全方面持续和可持续的经济发展。

Landslides in Canada are responsible for an average of four fatalities each year and cause ~$200 million of damage annually. Landslide management depends on government resources, and risk levels are evaluated through Factor of Safety, Probability of Failure, risk rankings or quantitative risk assessments. These risk levels can vary with time, and if their variability is not adequately understood and quantified, the likelihood of slope failures and their negative consequences can increase. Risk variability is attributed to the level of knowledge about the landslide, progressive degradation of materials, and external factors (particularly weather); however, limited studies address the fundamental processes behind risk variability with time. My previous work focused on the development of frameworks for quantifying landslide risk considering uncertainty for a variety of parameters. These frameworks were developed under the current state of knowledge regarding risk variability and were practical in nature. The proposed work will now advance the fundamental study of landslide risk variation with time, particularly in light of climate change, and assess the adequacy of landslide risk acceptability criteria. To the best of my knowledge, this research will generate new knowledge in the physics of landslide evolution, which will inform the development of practical approaches toward landslide risk management. The first objective is to understand the fundamental processes in landslide risk variation for two sites with different types of landslides: a compound landslide and a slope prone to rock falls. This work will develop a framework for estimating risk variations with changes in landslide deformation patterns and external factors, particularly in the context of climate change, and develop numerical realizations of the compound landslide to adapt the landslide risk analysis process to estimate seasonal and long-term risk variability. The second objective is to quantify the impact of model uncertainty when analyzing a cut-slope within a reservoir and to assess the adequacy of evaluation criteria at different stages of the life of a cut-slope (design, construction, operation, long-term). This work will monitor the slope through remote sensing coupled with in-situ instrumentation to faciliatate the development of an approach to evaluate uncertainty reduction and develop a numerical approach to estimate changes in slope behaviour in the long term to assess the most adequate slope risk criteria at different stages of the life of a cut-slope. The research program will train two PhD students and a Research Associate and will advance the fundamental understanding of seasonal and long-term changes in landslide risk, particularly associated with climate change. This will provide the basis for addressing current and future changes in landslide risk to assure continuous and sustainable economic development in terms of public and environmental safety.