Two dimensional sedimentation modeling in the Port of El Tablazo

Two dimensional sedimentation modeling in the Port of El Tablazo

Van der Wildt, H.

Booij, N. (mentor)
Kranenburg, C. (mentor)
Schiereck, G.J. (mentor)
Stere, C.L. (mentor)
Sokolewicz, M.J. (mentor)
D' Angremond, K. (mentor)

Civil Engineering and Geosciences

Hydraulic Engineering

1998-05-01

Due to increasing dredging costs, especially in ports and estuaries where the bed often contains contaminated substances, an increased tendency is observed to the investigation for more structural solutions to prevent deposition. Before however applying such engineering schemes a thorough knowledge of the sediment dynamics is needed. In the present model study, the attention was focused on the cohesive sediment transport in an estuary in the north-west of Venezuela. Here the Gulf of Venezuela has access to Lake Maracaibo through the very shallow Bay of EI Tablazo and The Strait of Maracaibo. The actual area of interest concerns The Strait of Maracaibo, in which the port of EI Tablazo is located. It was requested by the owner of this port to predict the morphological development in the port area in case no structural changes were made. For studying the sedimentation and the transport of cohesive sediment in The Strait of Maracaibo a two-dimensional depth integrated computational simulation model was used. This model, MIKE21, is a product of the Danish Hydraulic Institute and exists out of several modules to simulate hydrodynamics, wave fields, sand transport, mud transport and the spreading of environmental substances. The hydrodynamics for the area of interest were already simulated by a former HASKONING study, together with the primitive use of the mud transport module. The present study used the extensive features of the multi layer module. This module is able to simulate the transport, erosion and deposition of cohesive sediments by taking flocculation into account and describing the bed in several layers. Each layer has its own properties, concerning densities, erosion rates, bed shear strength etc. At first the presence of sufficient data, to describe the many model parameters, was assumed to be a prerequisite for the use of this module. However by the absence of sufficient data an extensive literature study has been carried out, with as main objective to determine appropriate numerical values for the unknown model parameters. The study ended up with morphological predictions for three cases: an average dry year, an average wet and an multi annual average year. The final morphological predictions were verified by means of sounding charts and concern the net deposition in the port area of EI Tablazo. The resemblance between the predicted deposition and the measured deposition is remarkably good, although it has to be realised as well that the model is only verified for a small area. Before proclaiming an accurate sediment model, in the future an extensive calibration phase for the whole model area should be carried out.

cohesive sediment transport
estuary
bed morphology

http://resolver.tudelft.nl/uuid:6cc9b57f-04d2-4e3b-a1df-2dae2c60bc54

Student theses

master thesis

(c) 1998 Van der Wildt, H.