无人机倾斜摄影三维模型在城市雨洪风险评估中的应用

研究城市雨洪风险问题，对提高城市洪涝灾害监测、预报的准确性，以及促进城市防洪决策制定具有重要的意义。鉴于高精度的城市三维模型可以提供丰富地理信息，便于准确分析淹没情况，本文针对当前城市洪涝模型对地形数据的高敏感性，且雨洪风险评估研究的准确性受限于地形数据精度的问题，提出利用无人机倾斜摄影测量技术重建高精度实景三维模型，并结合GIS的空间分析功能，以淹没深度为关键指标进行研究区的雨洪风险评估。通过提取不同重现期下研究区的淹没深度信息，进行可视化渲染实现三维淹没分析，可以直观地看到研究区的淹没情况，作为暴雨内涝风险管理依据，同时对城市规划布局有一定的参考价值。

Application of 3D modeling of UAV tilt photography in urban rain flood risk assessment

The study of urban rain flood risk issues is of great significance to improve the accuracy of urban flood disaster monitoring and forecasting, and to promote the decision-making process of urban flood control. Because the high-precision urban 3D models can provide rich geographical information, it is convenient for accurate analysis of flooding. With the aim to solve the problem that the current urban flood model is highly sensitive to terrain data and the accuracy of flood risk assessment research is limited by the accuracy of terrain data, this paper innovatively proposes to use UAV tilt photography technology to reconstruct high-precision real-world three-dimensional model. Combined with the spatial analysis function of GIS and the key index of submergence depth, we carry out flood risk assessment in the study area. By extracting the inundation depth information of the research area under different reproduction periods and performing visual rendering to realize the three-dimensional flooding analysis, the flooding situation of the research area can be visualized for the risk management of the urban rain flood, which also provides valuable reference for the urban planning.