Study On Dynamic Characteristics Of The Northern Wing Of The Radiant Sandbar

Radial Sand Ridges Area in the South Yellow Sea with muddy coast is in the middle part of Jiangsu coastal area. The morphodynamic process is complex and coastal evolution changed greatly. Under the background of Yellow River which is the sandbank north wing main sediment source flows to the north, the north wing of radial's Tidal flow field and sediment changed, which caused the attention of many scholars. Based on the application of RS, GIS and Delft3D mathematical model, this paper analyzed the coast's deposition and surface sediment characteristics,Combining macro landscape pattern, hydrological characteristics of dynamic field,sediment source and sediment discharge angles to discuss driving force of the evolution characteristics and predict it's evolution trend.According to the surface sediment data, analysis of sediment type, grain size parameters and their spatial distribution characteristics. The results show that the average particle size of WangGang coast Marine sediment in the range of 2.18?6.61?; Most sediment sorting coefficient is bigger than 1, sorting is poorer; Sediment particle size distribution curve is basically negative bias; Sediment peak state between 0.9?1.77, changes slightly; The average particle size of She Yang estuary Marine sediment in the range of 3.13?6.91?,Most sediment sorting coefficient is bigger than 1,sorting is poorer; Sediment kurtosis is very narrow.Through the analysis of the terrain data based on GIS and DEM method to analyzed the coast's scouring and silting characteristics. Studies showns that WangGang coast from 2006 to 2010, coastal net erosion rate of 0.007 m/a, the district is slowly eroded. Scour rate of the contour from land to sea presented by fast to slow and fast; In northern and central bank erosion intensity to the sea,South of coastal erosion, sedimentation characteristics to the sea; offshore slope gradually becomes steep.She Yang estuary from 2006 to 2013, net coastal sediment rate of 0.049 m/a,the district is erosion state. In addition to the channel place due to manual excavation of natural strong erosion, the overall performance for Coastal sedimentation, Offshore erosion, erosion and deposition of the profile shapes have obvious balance; Coastal tidal flat width increases, the underwater bank slope steep slope.Based on RS and discuss Delft3D mathematical model to discuss driving forces.Results show that under the trend of western waterway westward, offshore slope becomes sharp and Tidal flat gradually narrowed; WangGang coast coastal tide as obvious reciprocating flow, tidal water power is strong, She Yang estuary as a result of the Estuarine engineering construction, coastal tide morphological changed,hydrological and sediment environment becomes more complex.; Sediment transport trends are the net sediment outward, coastal is the erosion state.In conclusion, the sandbank north wing of erosion will expand further, Under the effect of topography and Tidal flow field, near waterways and bar will produce sediment deposition.