Muddy sediment erosion - insights from field studies

Studies on cohesive sediment erosion can be traced back to the mid-1950s, and since that time many of the benchmark papers describing the response of settled mud beds to fluid stress have been published in the Journal of Hydraulic Engineering. Relatively few main players, in particular three professors, have dominated the stage: R. Krone, A. Mehta, and E. Partheniades. Mehta and Partheniades continue to publish, but sadly Krone passed away in 2000. Their work has provided a cornerstone to cohesive sediment research, outlining the fundamental aspects of the erosion process as well as some of the controlling factors. Following recognition of the importance of the thixotropic properties of mud, there has been a move toward direct in-situ experimentation. Quite literally, the laboratory has been taken into the field. This has been possible through the development of field-portable or “benthic” flumes. Many of these developments have been published in the nonengineering marine scientific literature and have not come to the general notice of the engineering fraternity. The aim of this paper is to provide an overview of the knowledge gained from this work, highlighting both advances and shortcomings, and to place it within the contextual framework of the earlier studies of Krone, Mehta, Partheniades, and others.