| Abstract The goal of this note is to
examine a continuum theory that describes the evolution of sediment beds when subjected to
time-dependent shearing forces resulting from surface water movement. The bed was
conceptualized as a medium with continuously varying properties such as shear strength and
void ratio. The nonlinear equation describing finite strain consolidation, and the
complicated nature of the shearing forces acting on top of the bed, preclude the
possibility of analytical solutions. Ramifications of linearizing the governing flow
equations were explicitly evaluated for applications in bed modeling. Numerical solutions
were obtained for the linear and nonlinear models under transient boundary conditions.
Model results indicated that the linear model typically predicts lower void ratios, and
consequently underestimates the amounts of sediment eroded from the bed as compared to the
nonlinear model.
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