Study On Bedload Transport And Estimation Of Downstream Channels And Its Tributaries Of Jinshajiang River

The study on bedload transport characteristics is always a fundamental subject in the theoryof sediment transport. While the incoming sediment of the Changjiang River mainly origins fromthe downstream of Jinshajiang River. The characteristics of bedload transport and its estimationmethods in downstream of Jinshajiang River are studied in this thesis. Based on overview ofprevious researches and analysis of basin characteristics of Jinshajiang River downstream, bymeans of flume experiments and bedload transport rate formulae calculation, the bedloadamounts of the main channel and tributaries of this river reach have been estimated. Furthermore,the recommended estimation methods of bedload amount in Jinshajiang River downstreams havebeen proposed. The main contents of this thesis are as follows:(1) Overviewâ‘ It has an overview of the characteristics of bedload transport, including incipient motion,transport mechanism and their influencing factors, etc.â‘¡Estimation methods of bedload amount have been classified into observation andexperimentation, caculation by the formulae, correlative analysis,etc. It is of detailed describtionand comperhensive evaluation of these methods.â‘¢General situation of the river basin, flow and sediment transport characteristics ofJinshajiang River downstreams have been analyzed.(2) Estimation for Tributarysâ‘ Flume Experiments. Bedload of three typical tributarys in Jinshajiang River downstreams(i.e. Longchuanjiang River, Niulanjiang River and Xiaojiang River) have been studied mainly.Equilibrium sediment transport flume experimentations of these three tributary have been carriedout. Due to the analysis of the experiment results and the hydrographic data of control stations ofthese three tributary, the annual bedload amount of them has been calculated.â‘¡Calculation by Formulae. These three tributary'annual bedload amounts are calculatedby some formulae of bedload transport rate, which are of respective theoretical basis andextensive use in engineering practice. Finally, it has a suggestion that the formula of theChangjiang River Scientific Research Institute (CRSRI) is more suitable to such river reach.â‘¢Estimation for Other Tributarys. According to their hydrographic data from the controlstations, the annual bedload amount of other tributarys has been calculated by CRSRI formula.(3) Estimation for Main ChannelsOn the basis of the study results of the tributarys, and due to the analysis of bedload transport characteristics of the main channel, the methods to estimate the main channel bedloadamount of Jinshajiang River downstreams are summarized and classified. By means of thecorrelative analysis (accumulation along the river, correlation of flow amount, ratio of bedload tosuspension), the bedload amount of the main channel of Jinshajiang River Downstream havefinally been eatimated.