Field Research on the Influence of the Mixed Geotube Groin Construction on the Flow and Riverbed in the Yanguan Section of the Qiantang River Estuary
The temporary mixed geotube groin used for cofferdam construction in the reinforcement project of the foot of the ancient seawall on the north bank of the Qiantang River plays a crucial role in the progress of the project and the improvement of construction efficiency.However,currently,research on the water and sediment movement around geotube groin is rare,and there is a lack of relevant measurement data.This article considers the dynamic process of the construction of the mixed geotube groin,using unmanned aerial vehicle to capture water flow videos and LSPIV(Large Scale Particle Image Velocimetry)processing technology to analyze the flow field around the groin before,during,and after construction.The terrain near the groin is tracked and measured,and the sediment concentration of the water flow during different tidal ranges is measured on-site.It is found that the groin has the effect of changing the direction of water flow and reducing the erosion of river banks.The longer the spur dikes,the more obvious their jet flow effect,providing a relatively gentle water flow condition for cofferdam construction.The mixed groin has a significant effect on promoting sedimentation at the back of the dam,and the bed changes behind the dam are closely related to the sediment concentration.The larger the tidal range,the more sediment content the water carries,and the more relative sedimentation of the riverbed behind the geotube groin.The raised riverbed is also more conducive to improving the construction efficiency of the cofferdam.The present work can also provide data support for future research on related physical models and numerical simulations.
万方数据
维普
