Study On Bed Load Transport Characteristics Experiment In Fluctuating Terminal Of Backwater Region Of Three Gorges Reservoir

The Riverbed consisting mainly of gravel material in fluctuating terminal of backwater region of Three Gorges Reservoir. Chongqing City Reach is a typical mountain river bend river, within the scope of the main city of five consecutive corners.Pebble bed material is mainly sand and gravel, river border is very stability.Characterized by its navigation obstruction for bending, shallow, dangerous.Interaction of water, sediment greater impact on fluvial formation mechanism pebbles rapids more complicated. The upper reaches of the Yangtze River Sedimentation is mainly pebble bedload at work, the pebble bedload transport belt Fluctuating period may cause obstructs navigation. So the key technologies in channel regulation goes pebble qualitative changes in fluctuating terminal of backwater region of Three Gorges Reservoir. width and position of the gravel transport is particularly important.Through the establishment of a normal physical river model supplemented by a mathematical model of water form one seventy-terminal segment in fluctuating terminal of backwater region of Three Gorges Reservoir under each typical flow, bed load transport intensity, bedload transport with position and width characteristics test the study. Typical flow field obtained Beach each segment, changes in bedload transport belt position, distinguish moving sediment transport with transport and deposition with different intensity of bedload transport mode. The results were a lot of statistical analysis, a different way each transport segment Beach bedload transport at all levels with the flow and velocity, water depth, change characteristics than the drop.Finally unified into bedload transport belt and water flow intensity variation of power dimensionless numbers*W.Test Results: flow pattern under each Rapids typical flow analysis in fluctuating terminal of backwater region of Three Gorges Reservoir, bedload transport belt in motion characteristics of each Rapids. Changes characteristic transport belt*W summed move sediment transport stream power with universal values ??than the*W deposition of large transport belt, you can determine the intensity of moving sediment transport transport intensity is greater than the deposition, in the dry season and the water phase, transport with*W is significantly larger than the value of the big*W with no transport. Flood began, surface slope down transport decreases with*W averages.*W value with each transport to the Great Flood of changes to regional stability.Conclusion :*W value compared with moving silt sediment transport transport*Wvalue with the larger, indicating moving bedload sediment transport belt is the strongest way of transport, deposition, followed by transport.*W of the average of the water transport belt is about 2-2.5 times the average dry season*W, we can see that may arise bedload transport navigation obstruction caused by weakening of the Fluctuating period. Flood began, due to the reduced surface slope reasons,*W value with reduced transport, transport intensity decreased, indicating that changes will appear on in fluctuating terminal of backwater region of Three Gorges Reservoir, flood siltation,erosion flood stage late Fluctuating the bed load characteristics.