SETTLING CHARACTERISTICS OF FINE-GRAINED SEDIMENTS USED IN LOUISIANA COASTAL LAND BUILDING AND RESTORATION PROJECTS

摘要

As of 2012, the state of Louisiana has lost about 1,880 square miles of coastal land. One of the goals towards reestablishing a healthy coastal ecosystem is to rebuild wetlands with river diversion or sediment. Engineering properties and material characteristics of the dredged material and foundation soils are input parameters in several mathematical models used to predict the long term behavior of the dredged material and foundation soil. The sedimentation characteristics of the dredged material as well as their effects on the time rate of settlement of the suspended solid particles and underlying foundation soil depend, among other factors, on the (a) grain size distribution of the dredged material, (b) salinity (fresh, brackish, or saltwater) of the composite slurry, and (c) concentration of the solid particles in the slurry. This paper presents current methodologies used and advancements made in properly characterizing fine-grained sediments dredged and used in coastal restoration projects.