为适应现代化水库运行管理矩阵建设需求，进一步提升丹江口水库洪水预报预警能力，推动洪水预演可视化、预案精准化，本文基于MIKE和GIS软件，模拟了7种情景丹江口水库超标准泄洪时下游洪水演进情况，分析了不同情景下游区域洪水到达时间和洪峰到达时间，对比了洪峰水位、洪峰水量与典型断面设计水位、最大允许流量关系，研究了不同情景下游区域淹没范围和淹没深度。结果显示：工程调蓄作用下，襄阳及其上游的洪水均在2~10h内到达，宜城至沙洋段洪水在10~24h内到达，仙桃地区洪水约在两天后出现，各典型断面洪峰到达时间均超过68h；混凝土坝溃坝工况下，近坝山区的洪水漫延规律与调蓄情景相似，平原地区的洪水演进速度整体上比工程调控情景慢3h以上；突发超标准来水土坝溃坝工况，钟祥以上区域的洪水和洪峰分别在12h和18h内到达，钟祥以下区域的洪水和洪峰则分别在13h和31h后到达；丹江至宜城河段有较多漫堤险情。校核洪水、设计洪水、混凝土坝死水位溃坝和混凝土坝加高部分溃坝工况下，坝址至襄阳樊城大部分区域淹没深度为16~20m，天门下游淹没水深低于3m；特大洪水土石全溃工况，坝址至襄阳樊城区淹没深度约为35m，丹江口河段淹没深度超过50m；沙洋县洪水倒灌致潜江市超过70%区域被淹，整体淹没深度不超过2m。基于上述成果，本文研究为丹江口水库大坝安全管理应急预编制。洪水预演可视化和现代化水库运行管理矩阵的建设提供了有力的支撑。

With the completion of the second phase of the height-increasing project of the Danjiangkou Reservoir and the increase in the water diversion volume of the Middle Route of the South-to-North Water Diversion Project, significant changes have occurred in the engineering conditions, water conditions and underlying surface elements of the Danjiangkou Reservoir. Moreover, as the economy and society downstream of the Danjiangkou Reservoir develop rapidly, all sectors of society have paid more close attention to the safety management issues of the Danjiangkou Reservoir. At the same time, with the proposal of digital twin and modern operation management matrix construction requirements in recent years, the demand for visualizing the flood simulation process of Danjiangkou Reservoir, the evolution of downstream floods and inundation losses has gradually increased. It is necessary to re-analyze in combination with the latest topography, geomorphology, engineering conditions and water conditions, and simultaneously revise the emergency plan for the safety management of the reservoir dam. Therefore, in order to meet the demands of the construction of a modern reservoir operation and management matrix and further enhance the flood forecasting and early warning capabilities of the Danjiangkou Reservoir, this paper simulated the over-standard flood discharge scenario of the Danjiangkou Reservoir, analyzed the evolution and inundated conditions of the downstream flood, with the aim of promoting the visualization of flood forecasting and the precision of emergency plans. Provide stronger support for ensuring the safety of the Danjiangkou Reservoir Project and water supply security. Based on the principles of the continuity equation and the momentum equation, this paper uses the Mike series model software to construct a two-dimensional hydrodynamic model of the downstream river channel and floodplain. Fully considering the impact of flood evolution on key cities downstream, a computational grid is constructed based on DEM and measured terrain to simulate the flood evolution of the downstream when the Danjiangkou Reservoir over-standard discharge occurs under seven scenarios. The arrival time of flood and peak flood in the downstream area under different scenarios were analyzed. The relationship between peak flood water level, peak flood water volume and the design water level and maximum allowable flow of typical sections was compared. Based on GIS software, the inundation range and inundation depth in the downstream area under different scenarios were analyzed and studied. The results show that under the regulation and storage effect of the project, the flood in Xiangyang and its upstream reaches within 2 to 10 hours, the flood in the Yicheng to Shayang section reaches within 10 to 24 hours, and the flood in Xiantao area appears approximately two days later. The arrival time of the flood peak at each typical section exceeds 68 hours. Under the condition of concrete dam failure, the flood spread pattern in the mountainous area near the dam is similar to the regulation and storage scenario, while the flood evolution speed in the plain area is generally more than 3 hours slower than that in the engineering regulation and control scenario. In the case of sudden over-standard water inflow and earth dam failure, the flood and flood peak in the area above Zhongxiang will arrive within 12 hours and 18 hours respectively, while in the area below Zhongxiang, they will arrive after 13 hours and 31 hours respectively. There are many risks of embankment overflow in the section from Danjiang to Yicheng. Under the conditions of verification flood, design flood, dead water level failure of the concrete dam and failure of the elevated part of the concrete dam, the submergence depth of most areas from the dam site to Fancheng, Xiangyang is 16-20 meters, and the submergence water depth downstream of Tianmen is less than 3 meters. In the case of a severe flood where all soil and rocks have collapsed, the submergence depth from the dam site to Fancheng District, Xiangyang City is approximately 35 meters, while the submergence depth in the Danjiangkou section exceeds 50 meters. The flood in Shayang County caused over 70% of the area in Qianjiang City to be inundated, with the overall inundation depth not exceeding 2 meters. Based on the above achievements, this paper studies the emergency pre-preparation for the safety management of the Danjiangkou Reservoir Dam. The construction of a visualized flood rehearsal and a modern reservoir operation management matrix provides strong support.