Formulae for sediment transport rate of pebble bed load in Sanduizi reach of Jinsha River downstream
After the impoundment of cascade reservoirs in the upper and middle reaches of the Jinsha River,the suspended sediment transport in the lower reaches is reduced significantly,and conditions of water and sediment change obviously,which has a significant impact on the reservoir sedimentation process and makes the role of peb-ble bed load more important in the total sediment transport.Therefore,it is of great of significance to carry out the law of pebble bed load transport in the lower reaches of the Jinsha River under new water and sediment conditions,and to put forward the applicable incipient velocity and transport rate of pebble bed load.Based on the measured data at Sanduizi Hydrological Station from 2008 to 2021,the classical incipient velocity formula and bed load trans-port rate formula are tested and corrected.The result shows that compared with classical formulae,the calculation accuracy of the modified formula is significantly improved by introducing a coefficient with the particle size as a vari-able,which induces different particle size ranges.Meanwhile,the results of classical bed load transport rate devi-ate greatly from the measured values when the sediment transport intensity is low.By establishing the intensity rela-tionship of sediment transport and water flow and introducing hidden parameters to modified formula,the calculation accuracy of low sediment transport rate is also obviously improved.The transport law of pebble bed load in Sanduizi reach can bed more effectively reflected by the modified formulae of incipient velocity and bed load transport rate.
lower reaches of Jinsha Rivercascade reservoirpebble bed loadincipient velocitypebble bed load transport rate
万方数据
维普
