Erosion And Siltation Research On Zhuhai Power Plant Channel And Its Nearby Area

Channel as ships’ entrance to harbor plays a significant role in port construction and operation. However, many channels and ports throughout the world suffer from siltation, requiring maintenance dredging activities to safeguard required depths. This paper simulated the rules of erosion and siltation of Zhuhai Power Plant Channel and its nearby area, analysed the characteristic of sediment transport, and studied the impact of dynamic factors such as tide, wave and wind and engineering factors on erosion and deposition. The main work and conclusions are as follows:(1)A 2D horizontal sediment numerical model was built and validated to simulate the rules of erosion and siltation of Zhuhai Power Plant Channel and its nearby area.(2)The erosion area showed zonal distribution from Damangdao-Sanjiaoshan-Nanshuidao Section to Hebaodao-Gaolandao Section with the deposition area lying on both sides. More areas tended to be deposited during both flood and dry seasons, but more siltation during flood season and more erosion during dry season compared with each other. The siltation intensity along the Zhuhai Power Plant Channel was characterized by the phenomenon that the intensity in middle was larger than that at both ends. The maximum and average siltation intensity were 0.89m/a and 0.59m/a respectively during flood season while 0.81m/a and 0.49m/a respectively during dry season.(3)The volume ratios of sediment transported into Gaolan Port from Sanjiaoshan-Nanshuidao Section, Damangdao-Sanjiaoshan Section, Hebaodao-Gaolandao Section and Hebaodao-Damangdao Section were 2.9:9.2:8.5:1 and 10.8:26.3:11.2:1 during flood season and dry season, respectively. The volume ratios of sediment output from this four sections were 0.5:1.1:1.9:1 and 1.5:2.6:2.9:1.Damangdao-Sanjiaoshan-Nanshuidao Section and Hebaodao-Gaolandao Section are the main waterways for sediment transportation.(4)The impacts of tide, wave and wind on erosion and deposition were studied and the results showed that wave was the main dynamic factor.(5)The breakwater had a significant effect on weakening Zhuhai Power Plant Channel’s siltation by reducing the maximum and average siltation intensity. The impact was becoming more obvious with the breakwater being lengthened while the amplitude was decreasing. Whether the siltation intensity could be further reduced by lengthening the breakwater needed a further study and research.