Wang Jun, Garg Ankit, Huang Shan, Wu Zhiwen, Wang Tiancheng, Mei Guoxiong
Key Laboratory of Disaster Prevention and Structural Safety of a Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Structural Safety, College of Civil Engineering and Architecture, Guangxi University, Nanning, 530004, China.
Guangdong Engineering Center for Structure Safety and Health Monitoring, Shantou University, Shantou, 515063, China.
Environ Sci Pollut Res Int. 2022 Feb;29(7):10482-10494. doi: 10.1007/s11356-021-16369-x. Epub 2021 Sep 15.
Improving the rainwater retention capacity (RRC) of green roofs has been proposed as an important component of urban stormwater management. In this study, a two-layered soil green roof model was established to enhance RRC compared to each single soil column model. The hydrological process of layered soil green roofs was simulated using the HYDRUS-1D program, with simulation results verified by measured results. The results showed that the RRC of the layered soil was 5% and 1% higher than that of each single substrate under a long-term dry-wet cycle and increased by 15% and 11% per event compared with the single substrates. In addition, higher peak drainage reduction and longer peak drainage delay were observed in the layered soil green roof compared to each single soil. The layered soil slowed the movement of the soil wetting front and increased the maximum water content of the upper soil. The water loss of the layered soil was reduced after rainfall and mainly occurred in the lower layer of the layered soil. These results suggest that the structures of green roofs with an upper layer with higher permeability and a lower layer with lower permeability have better hydrological performance.
提高绿色屋顶的雨水保持能力（RRC）已被提议作为城市雨水管理的一个重要组成部分。在本研究中，建立了一个双层土壤绿色屋顶模型，以与每个单一土壤柱模型相比提高RRC。使用HYDRUS-1D程序模拟了分层土壤绿色屋顶的水文过程，模拟结果通过实测结果进行了验证。结果表明，在长期干湿循环下，分层土壤的RRC比每个单一基质分别高5%和1%，与单一基质相比，每次降雨事件的RRC分别增加15%和11%。此外，与每个单一土壤相比，分层土壤绿色屋顶的峰值排水量减少更高，峰值排水延迟更长。分层土壤减缓了土壤湿润前沿的移动，并增加了上层土壤的最大含水量。降雨后分层土壤的水分损失减少，主要发生在分层土壤的下层。这些结果表明，具有上层高渗透性和下层低渗透性结构的绿色屋顶具有更好的水文性能。
