不同汛前水位控制方案下平原新城竖向标高研究——以江苏省丹阳市为例

Research on vertical elevation in new area of plain city under different flood water level control schemes before flood season:case of Danyang City,Jiangsu Province

为确定平原河网新建城区的地面基准建设标高,以江苏省丹阳市练湖新城汇水区为研究对象,在50 a一遇城市设防标准下,通过MIKE 11水动力模型与ArcGIS土方挖填分析工具,研究高、低两种不同汛前水位控制方案对最高设计水位与场地竖向方案的影响,并从安全保障、土方平衡、挖填面积以及亲水性4个方面对两个方案进行综合比较。研究结果表明:两种方案均能保证排水的安全性,但相较于汛前高水位方案,低水位方案最高水位控制低、峰现时间延长、土方缺口较小、挖填面积较小,更适宜练湖新城的建设。通过城市水系最高水位控制与场地竖向的挖填方耦合分析,为南方平原地区的新城建设竖向基准标高确定提供了参考思路。

In order to determine the ground datum construction elevation of the new urban area of plain river network,this paper took the Lianhu new town catchment area of Danyang City,Jangsu Province as the research object.On the premise of meeting the flood control standard of a 50-year flood,the influence of high and low flood water level control schemes before flood season on the maximum design water level and site vertical scheme was studied by MIKE 11 hydrodynamic model and cut/fill module of ArcGIS software.And then the two schemes were compared from four aspects:safety guarantee,earthwork balance,excavation and filling area and harmony water-human relation.The results showed that both two schemes can ensure the safety of drainage,but compared with the high water level control scheme,the low water level control scheme was more suitable for the construction elevation of Lianhu new town due to its lower maximum water level control,delayed peak time,smaller earthwork gap,and smaller excavation and filling area.Through the coupling analysis on the highest water level control of urban water system and the vertical elevation of the site,it can provide a reference for the determination of the vertical datum elevation of new towns’construction in the southern plain area of China.