ABSTRACT
This chapter describes the theoretical basis and physical background to the Shiono & Knight Method (SKM) which was introduced in Chapter 2, Sections 2.3 to 2.5. The derivation of the governing equation, (2.58), is now fully documented, as are how to obtain analytical solutions, with Appendices 4 to 6 providing additional material. The schematization of river cross sections is considered in relation to the physics of the flow, as are the choice of appropriate boundary conditions. The roughness and hydraulic resistance of channels with floodplains are examined, including the drag forces that occur on trees. The distribution of boundary shear stresses around the wetted perimeter of river channels is highlighted, along with the implications for sediment transport and morphology. The SKM is used to illustrate the link between flood wave speed and the channel and floodplain geometry, and its use in extending the wave speed relationship to discharges higher than actually observed. The Chapter concludes with a summary of some further applications of the SKM in river engineering, before considering these in detail in Chapter 7.
