Dolgu barajlar örneğinde baraj yikilmasina bağli taşkin tehlike haritalarinin CBS ve matematik modeller üzerinden oluşturulmasi ve değerlendirilmesi

Dam hazard analysis is a key component of dam failure mitigation and disaster post-management. Many dams have either no hydro-meteorological data available or very little associated only with the hydraulic structure's planning phase. These data inadequacy causes major difficulties in performing hazard analyses. In the presented study, a combined hydrologic and hydraulic modeling approach is developed in a novel analytical framework for evaluating dam break issues in cases of ungauged basins. The study is aimed to provide an operational framework that allows engineers and specialists to understand, simulate and then manage the phenomenon of dam failure. The framework consolidates the application of synthetic unit hydrograph concept, hypothetical hyetograph estimation, distributed hydrological modeling, and hydraulic dam break simulation approaches. The study benefits from a dynamically downscaled climate model of 1km resolution to perform extreme precipitation frequency analysis, resulting in grid-based Intensity-Duration-Frequency (IDF) curve featured in spatially-distributed design hyetograph generation. The framework also adopted the climate change effects to decrease the uncertainties in both the design and risk assessment phases. An application of the two-dimensional hydrodynamic model is utilized to model the flood wave evolution resulting from varying dam-break events. In this respect, an alternative scenario-based approach is adopted in order to quantify differences in flood depth, velocity and arrival time of flood waves under various dam-break conditions. The simulation shows that both downstream regions are subject to significant potential risks against dam-break with the figure of more than 80% of the inundation area classified as a high-risk zone.