Time-dependent sediment transport subjected to downward seepage

Abstract

Experiments were conducted using cohesionless sand particles with median diameter of 0.48 mm to investigate the time variation of sediment transport rate under the influence of local downward seepage. The experimental results show that the bedload transport rate in terms of volumetric sediment transport rate per unit width increased rapidly with time in the presence of suction, eventually reaching a peak beyond which it started to decrease. The trend of reduction was significantly reduced beyond 8 400 s after the test started. The analytical expression was derived in terms of dimensionless sediment transport rate and dimensionless time. The hypothesized relationships were compared with the experimental data, indicating a good agreement with each other.

Keywords

time effect / suction / seepage / sediment transport rate

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