Studies of recent decades have shown thousands of kilometers of transportation networks that have presented damage or failure from different types of flows, causing important traffic disruptions. Debris flows running adjacent (or in parallel) to river channels often explain the structural damage to road embankments caused by slope erosion. The probability of expected structural damage caused by a natural hazard may be modeled using fragility curves, which have been developed for transportation infrastructures like bridges and roads exposed to debris flows and are used in risk assessment. There are even fragility curves available to estimate the fragility of road embankments exposed to perpendicular debris flows. However, currently no model is available to estimate the road damage probability of embankments exposed to adjacent debris flows despite their important effects on traffic. This paper aimed to develop fragility curves for road embankments exposed to adjacent debris flows, considering mechanisms of exposed slopes subject to erosion and subsequent embankment instability. Models were calibrated considering flow characteristics in straight and bend channels including three damage states in terms of road traffic capacity loss. Monte Carlo simulations were performed to model potential damage, obtaining fragility curves for two types of roads. Curves were fit to log-normal distributions with a 99.5% confidence level. The analysis demonstrated that the geometric characteristics of road embankments explain their fragility, wherein lower heights and platform widths result in more probable expected damage. The analytical model developed confirmed that the erosive process intensifies in bend zones of channels, resulting in higher damage probability.

近几十年的研究表明，数千公里的交通网络已经因不同类型的流量而出现损坏或故障，从而导致严重的交通中断。与河道相邻（或平行）流动的泥石流通常可以解释斜坡侵蚀对路堤造成的结构性破坏。自然灾害造成的预期结构损坏的概率可以使用脆弱性曲线建模，该曲线已针对暴露于泥石流的桥梁和道路等交通基础设施开发并用于风险评估。甚至有脆弱性曲线可用于估计暴露于垂直泥石流的路堤的脆弱性。然而，目前没有可用的模型来估计暴露在相邻泥石流中的路堤的道路损坏概率，尽管它们对交通有重要影响。本文旨在为暴露在相邻泥石流中的路基制定脆性曲线，考虑暴露边坡受到侵蚀和随后路基不稳定的机制。模型的校准考虑了直通道和弯通道中的流动特性，包括道路交通容量损失方面的三种损坏状态。进行蒙特卡罗模拟以模拟潜在损坏，获得两种类型道路的脆弱性曲线。曲线符合对数正态分布，置信水平为 99.5%。分析表明，路堤的几何特征解释了它们的脆弱性，其中较低的高度和平台宽度会导致更可能的预期损坏。建立的分析模型证实，侵蚀过程在通道弯曲区域加剧，导致更高的损坏概率。