PREDICTION ON MORPHOLOGICAL RESPONSE OF DREDGED SAND-BORROW PITS

Qimiao Lu, Robert B. Nairn

Abstract


Dredged pits in coastal zones are generally required for sand borrows for beach nourishment. The morphological response of borrow pits is important to evaluate future environmental impacts and potential impacts to adjacent seabed infrastructure such as pipelines. This paper will present the development of a simple concept model for the prediction of morphological response of dredged pits. A 3D hydrodynamic and sediment transport model was applied to verify the developed simple concept model. The case study for a sand-borrow pit on the offshore of Louisiana at the Atlantic coast of USA will be updated. The strengths and limitations of the developed model will be also discussed.

Keywords


sand-borrow pits; sedimentation; margin erosion; sediment transport modeling; morphological modeling; empirical formulae

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