摘要
针对长三角地区城市浅水湖泊面临景观水体污染物易于富集、难于扩散、水质较难保障的现实困境,阐述了以学科融合为基础的水体污染物扩散模拟与循证设计,提出地形作为水体形态的骨架对水动力条件的形成、湖泊水环境的改善起到关键性作用.以常熟市琴湖为例,基于湖岸线、湖底地形、岛屿、堤坝等要素,提出2种平面形态和6种三维形态,通过Delft3D模型模拟的方法,分析比较不同三维形态下的流场特征,并输入实测数据得到20天后湖泊水深平均流速与污染物总氮(TN)扩散模拟结果.研究发现:1)湖泊岸线与湖底地形变化通过流场影响污染物扩散;2)曲折度较大的岸线应尽量安排在水流的主方向上;3)岛屿设计应体量适宜、与岸线距离合适;4)长堤割裂湖体形态时,建议堤坝下部设置连通管道.研究有助于筛选对水质保持有利的设计方案,也可为城市湖泊景观水体的循证设计提供一定的技术支撑与参考.
In response to the existing difficulty of the accumulation of pollutants and the maintenance of water quality in the shallow lakes in the Yangtze River Delta,this research clarified that the diffusion stimulation of water pollutants and evidence-based design based on inter-discipline,and proposed the critical role of terrain grading that shapes the configuration of water in influencing hydrodynamics and improving water environment of lakes.The research selected the Qin Lake in Changshu as case study.Based on the elements of the landform of lake bottom,shoreline,island and causeway,this research proposed 2 types of two-dimensional configurations and 6 types of three-dimensional configurations.By using the Delft3D software model,this research analyzed and compared different flow field characters,input the measurement data of TN,and stimulated the depth-averaged velocity and the pollutant diffusion after 20 days.This research found that:1)the changes of a lake’s shoreline and bottom terrain can influence the pollutant diffusion via flow field;2)more curvilinear shoreline should be arranged align with the main direction of water flow;3)island design should pay attention to suitable size and distance to the shore;and 4)connection pipes should be set up in the bottom of causeway if the causeway divides the lake into parts.This research was beneficial to select better design alternative that helps water quality maintenance,and provided technical support and reference for the evidence-based design of landscape water of urban lakes.
作者
汪洁琼
陈奕
毛永青
王敏
WANG Jieqiong;CHEN Yi;MAO Yongqing;WANG Min
出处
《中国园林》
CSCD
北大核心
2021年第5期44-49,共6页
Chinese Landscape Architecture
基金
国家重点研发计划课题(编号2017YFC0505705)
启迪设计科技计划项目“‘循证设计’理念在景观项目中的应用研究”共同资助。
关键词
风景园林
城市湖泊
景观水体
三维形态
Delft3D
污染物扩散模拟
水生态
landscape architecture
urban lake
landscape waterbody
three-dimensional configuration
Delft3D
pollutant diffusion simulation
water ecology
