The development of compound inundation analysis model in urban area and its application

本文研究的重点是城市内涝问题。论述了复合淹没分析模型的发展及其在各种淹没措施中的应用。本研究之结果如下：1）探讨市区内迳流淹水之分析模式，并分析东海大雨对名古屋市之淹水情形。研究发现，在合流制发展的城市地区，从地面到下水道的落差流量的评估对于淹没分析是非常重要的。2）研究了考虑下水道系统的淹没分析模型在水灾害对策中的应用。研究内容包括排水系统对淹水的影响、污水的分布等，特别是淹水时的卫生问题的检验结果。3）所建立的分析模型同时考虑了海域、河流和城市的水行为。利用本文所处理的分析模型，对洪水与风暴潮的重叠进行了检验。4）海湾地区的大城市多采用合流制排水系统，在排水过程中受河流水位（或潮位）的影响较大。在这里，海平面上升，由于全球变暖的影响，由于内部径流淹没进行了检查。因此，海平面上升小于1.0m时，对内涝影响不大。但是，当全球变暖导致雨强增大时，海平面上升的影响会显现出来。5）对分析网格中考虑微地平面的淹没分析模型进行了检验，验证了模型的适用性。

The focus of this study is inundation due to interior runoff in urban area. The development of compound inundation analysis model and its application to various measures for inundation are discussed. The results of this study are shown below.1) Analysis model for the inundation due to interior runoff in urban area was examined and inundation situation of Nagoya city due to Tokai heavy rain was analyzed. From this study, it is found that the evaluation of the fall flow quantity from overland to sewer was very important for inundation analysis in the urban area where combined sewer system developed.2) An application of the inundation analysis model considered sewer system to the measures for water disaster was examined. The topics are the effect of the sewer system to inundation, distribution of the filthy water, and so on. In particular, the examination results for the issue of hygiene during inundation were shown.3) The developed analysis model dealt with the water behavior in sea area, river area and urban area simultaneously. The overlapping between flood and storm surge was examined by using the analysis model treated here. From this study, the importance of the water gate for storm surge was shown.4) Many big cities located in bay area have the combine-sewer system and are affected by the river water level (or, tide level) in the drainage process. Here, influence of sea level rise due to global warming to the inundation due to interior runoff was examined. As a result, the sea level rise less than 1.0m does not give much influence to the inundation due to interior runoff. However, if rain intensity becomes high due to global warming, the influence of sea level rise appears greatly.5) The inundation analysis model considered micro ground level in analysis grid was examined and its applicability was verified.