考慮河道分洪的灰綠耦合設施改造方案研究

張朝陽1,方宏遠12,狄丹陽1,賈浩1,白渝1

1.鄭州大學水利與交通學院,450001;2.黃河實驗室,450018

摘要強降雨事件所引發的城市河道漫堤使得城市內澇災害愈發難以應對。為此,開展了考慮河道分洪的灰綠耦合設施改造方案研究,首先,針對下墊面、排水系統、河道三個方面分析研究區內澇成因,其次,利用改進NSGA-Ⅱ算法的TOPSIS法得到灰綠耦合設施最優改造方案,最后,對比分析改造前后研究區的內澇淹沒特征。主要得到以下結論:內澇成因主要為不透水用地類型占比較高、管道排水能力不足、金水河河水漫流;考慮河道分洪的灰綠耦合設施改造方案能夠有效減少城市內澇災害,50a降雨情景下內澇災害減弱效果最突出,積水深度減少了0.41 m,淹沒范圍減少了14.4 %,相當于441個國際標準足球場;灰綠耦合措施對于極端強降雨所產生的內澇災害削減效果一般。

關鍵詞城市內澇;灰綠耦合設施;河道分洪;多目標優化;TOPSIS

Study on the reconstruction scheme of gray-green coupling facilities considering river flood diversion

Zhang Zhaoyang1,Fang Hongyuan12Di Danyang1,Jia Hao1,Bai Yu1

(1.School of Water Conservancy and Transportation, Zhengzhou University, Zhengzhou 450001,China; 2.Yellow River Laboratory, Zhengzhou 450018,China)

Abstract: The flooding of urban rivers caused by heavy rainfall events has made urban waterlogging disasters increasingly difficult to deal with. To this end, a study on the transformation plan of gray-green coupling facilities considering river flood diversion was carried out. First, the causes of waterlogging in the study area were analyzed from the three aspects of underlying surface, drainage system and river channel. Secondly, the TOPSIS method of the improved NSGA-Ⅱ algorithm was used to obtain the optimal transformation plan of gray-green coupling facilities. Finally, the characteristics of waterlogging in the study area before and after the transformation were compared and analyzed. The main conclusions are as follows: the causes of waterlogging are mainly the high proportion of impervious land types, insufficient pipeline drainage capacity, and overflow of Jinshui River; the transformation plan of gray-green coupling facilities considering river flood diversion can effectively reduce urban waterlogging disasters. The waterlogging disaster reduction effect is the most prominent under the 50-year rainfall scenario, with the waterlogging depth reduced by 0.41m and the flooding range reduced by 14.4%, equivalent to 441 international standard football fields; the gray-green coupling measures have a general effect on reducing waterlogging disasters caused by extreme heavy rainfall.

Keywords: urban waterlogging; gray-green coupling facilities; river flood diversion; multi-objective optimization; TOPSIS

近年來,城市內澇災害問題日益突出。強降雨事件所引發的城市河道漫堤使得城市內澇災害愈發難以應對,給人們的生活、財產和城市基礎設施帶來了巨大的威脅。如,20237月,中國北京市發生嚴重內澇災害,永定河水位急劇上漲,小清河橋發生垮塌,漫溢的河水沖走大量汽車[1]

灰綠設施融合了灰色基礎設施的可靠性綠色基礎設施的可持續性對于城市內澇災害的治理具有重要的作用。然而,現有灰綠耦合設施改造方案研究大多只針對排水管道、綠色屋頂、透水鋪裝等進行改造,忽視了河道漫流所引發的城市內澇災害,未針對河道漫流問題提出具體的改造方案。

為此,本文開展考慮河道分洪的灰綠耦合設施改造方案研究,在充分分析內澇成因的基礎上,針對性地提出適宜于本研究區特點的灰綠耦合設施改造方案。

1 城市暴雨內澇模型

1.1 研究區概況

金水河是鄭州市中心城區的主要河流,為賈魯河主要三級支流。金水河由西南向東北流經二七區、中原區、金水區及鄭東新區,河道全長27.66 km,流域面積80.1 km2,是中心城區主要的行洪排澇通道之一,也是鄭州市唯一串聯四主城區的城市內河,其防洪保護對象尤為重要。研究區包含金水河和賈魯河兩條河流,賈魯河河岸兩側多為裸土或耕地,而金水河河岸兩側多為建筑物,人口和房屋密度較大,容易遭受暴雨內澇災害,如圖1所示。

1 研究區概況圖

研究區基礎數據包括:(1)排水管網數據:來源于《鄭州市排水工程規劃(2011—2020