Use of Perturbation Theory for Determination of Sediment Carrying Capacity in a Tidal River

In a fluvial river, coastal tides often carry suspended load that dominates in the sediment transport. The sediment carrying capacity (SCC) is the amount of suspended load carried by the flow and reflects the erosion and deposition equilibrium in the water body. Based on the perturbation theory, the study proposes a method for its determination and applied it to a natural river where tides play a predominant role. Taking into account such factors as flow velocity, water depth, particle settling velocity, median grain size and tidal range, a capacity formula is derived by means of dimensional analysis and multivariate linear regression. Extensive field data are collected to both determine and validate the coefficients. The practice is an improvement compared with the previous studies in which fewer parameters were used for correlation analysis. The proposed method has reference values to the study of SCC in other similar tidal rivers.

Keywords: sediment carrying capacity; tidal river; perturbation theory; suspended load; field measurements.