生物滞留设施排空时间影响因素研究

生物滞留设施是我国海绵城市建设中应用较为广泛的技术措施之一，在其设计和运行维护过程中，排空时间对雨水径流总量的控制效果、植物生长状况等具有重要影响，但目前尚缺乏排空时间影响因素的系统研究。通过实验室试验，研究了调蓄水深、降雨间隔、淹没区高度及构造类型对排空时间的影响。结果表明：试验条件下，不同构造类型生物滞留设施调蓄层排空时间为10~140 min，完全排空时间为6~47 h。调蓄层排空时间随调蓄水深和淹没高度的增加而增加，随降雨间隔的增加而降低，调蓄水深对调蓄层排空时间影响最大；完全排空时间随调蓄水深和降雨间隔的增加而增加，随淹没高度的增加而降低，降雨间隔对完全排空时间影响最大。研究结果可为海绵城市建设过程中生物滞留设施优化设计提供技术支撑。

Study on the influencing factors of emptying time of bioretention facilities

Bioretention facilities are one of the measures widely used in sponge city construction in China. During the design, operation and maintenance of bioretention facilities, the emptying time has an important influence on the total runoff volume control efficiency and plant growth. However, there is a lack of systematic research on the influencing factors of emptying time. The effects of storage-layer height, rainfall interval, submerged-area height and structure type on the emptying time were investigated via laboratory experiments. The results showed that under the test conditions, the discharge time of the storage layer of different structure types of bioretention facilities was 10-140 min, and the complete discharge time was 6-47 h. The emptying time of the storage layer increased with the increase of the storage-layer water depth and the submerged-area height, and decreased with the increase of the rainfall interval. The emptying time of the storage layer water was affected most significantly by the storage height. The total emptying time increased with the increase of water storage water depth and rainfall interval, and decreased with the increase of submerged-area height. The rainfall interval had the greatest effect on the total emptying time. The research results could provide technical support for the design and optimization of bioretention facilities in the process of sponge city construction.