Theses and Dissertations

Issuing Body

Mississippi State University


McAnally, William H.

Committee Member

Hayter, Earl J.

Committee Member

Martin, James L.

Date of Degree


Document Type

Dissertation - Open Access


Civil Engineering

Degree Name

Doctor of Philosophy


James Worth Bagley College of Engineering


Department of Civil and Environmental Engineering


Ports and waterways are vital to the economy of the United States. In the contiguous United States, there are some 25,000 miles of channels and over 300 ports. Together, this system carries 2 billion tons of freight with a value of over $700 billion annually. Ninety percent of all United States imports and exports travel through these ports and waterways. Dredging of these waterways in the United States costs over $1 billion annually. As ship draft increases, more dredging would be required to keep these ports and waterways open. Fine sediments are very common in these systems and have properties that can reduce dredging efficiency, including easy resuspension into the water column and cohesion among individual particles. Fluid mud is a high concentration aqueous solution of fine sediments that exhibits unique properties, including movement under gravity. A numerical model of fluid mud could be used to predict sediment fate as well as evaluating potential channel modifications to reduce dredging. The goal of this research is to test the flow of fluid mud under shear from the water column and develop a numerical model to simulate the transport of fluid mud. First, laboratory experiments are conducted to ascertain the effects of shear from the water column on the fluid mud layer. Next, a finite element numerical model is developed to simulate the physics of fluid mud, including any effects from shear over the mud layer. Results from the numerical model are compared to laboratory experiments, and the fluid mud model is developed for easy linkage to existing hydrodynamic models for forcing information.