Study On River Bed Erosion Below Changzhou Reservior In Xunjiang River

The construction of reservoir is the main mearment of general water resours untilization, it can possess much efficiency such as flood control, power generation, irrigation and so on.The constraction and operation of water conservancy work will influence its downstream reach greatly, among river bed erosion is the one must be considered and studied in course of hydraulic works'feasibility reseach for its vast area and long time impact.The bed erosion may bring a negative effect of deteriorate the navigation chanel. The works of Study on the problem of rivebed evolution is of great significance to the hydraulic project's programmed aim and the economical development in the river basin. With the methods of statistic and calculation, theory analysis , river simulation etc, this thesis mostly studies on the River Bed Erosion Blow Changzhou Reservoir of the xunjiang River . The main achievements are as follows:(1) A general presentation is given on the negative effect to the navigation by river bed erosion in downstream. And a brief introduction and review is also given about the presently research in downstream.(2) With the method of pattern recognition and fuzzy cycle, this dissertation chooses the water sediment representative years of Wuzhou reach in Xijiang River.(3) Based on the riverbeds compositions and the water and sand changes after the construction of reservoir, this thesis predicts the tendency direction of the riverbed evolution. On Changzhou to Jieshou section, the band and bed material composition condition is stabilization, so the bed changes would not exquisite. With the theory of armoring-layer size distribution, the securable utmost bed erosion value is caculated in the research section. The result illustrated the must bed erosion is just 86cm.(4) 2-D hydrodynamic-commercial software named SMS was applied into numerical simulation of bed erosion. With the modol, some work is done on a generalized river channel about erosion.