Procedures for Prediction of Consolidation in Soft Fine-grained Dredged Material


Book Description

The report documents studies refining the procedures for calculation of one-dimensional consolidation behavior of very soft fine-grained dredged material. Both the conventional small strain theory of consolidation, which requires linear or constant soil properties, and the more general finite strain theory, which provides for nonlinear soil properties, are presented. Implications of the simplifying assumptions necessary in practical application of the theories are discussed and the general finite strain theory is shown to be superior for the treatment of dredged material. The governing equations for both theories are written in nondimensional terms and appropriate boundary and initial conditions are specified. Solutions in terms of figures relating the percent consolidation to the nondimensional time factor for small strain theory have been previously published. However, similar solutions based on the finite strain theory were not available and thus had to be developed. Using a computer program, a linearized nondimensional form of the general finite strain governing equation was solved for the cases of singly/doubly drained normally consolidated clays, and singly/doubly drained dredged fill. The figures given represent a significant advancement in the ability to accurately predict the consolidation behavior of thick deposits of very soft fine-grained materials having nonlinear soil properties. A method of obtaining soil parameters necessary for use of the new solution charts is proposed. (Author).







Mathematical Model of the Consolidation/desiccation Processes in Dredged Material


Book Description

This report documents the development of a mathematical model of the consolidation/desiccation process in soft, fine-grained soils such as dredged material; provides for computer solution of the model; and verifies the solution through comparisons with field measurements.







Tidal Hydraulics


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Management Plan for the Disposal of Contaminated Material in the Craney Island Dredged Material Management Area


Book Description

The Craney Island Management Plan was developed to extend the life of the Craney Island Dredged Material Management Area (CIDMMA). The CIDMMA is used to dispose maintenance and new work dredged material from the project area. With current practice, CIDMMA would reach ultimate capacity by the year 2000. If, however, suitable material is barged to the sea and only contaminated material is placed in the facility (Restricted Use Program), then the life of the facility can be extended. Two tasks were addressed in this study: (a) determine service life under Restricted Use and (b) determine contaminant losses and conduct a Comprehensive Analysis of Migration Pathways (CAMP) expected to occur under Restricted Use. The results showed that the service life of the CIDMMA could be extended under Restrictive Use for approximately 140 years under baseline coniditions or 90 years under Worst Case conditions. The CAMP analysis was conducted along three major contaminant migration pathways (effluent, leachate, and volatile). Effluent was the most significant pathway for metal losses and volatilisation and for polynuclear aromatic hydrocarbon (PAH) losses. Leachate losses under a fully dewatered condition would not exceed effluent losses for some metals. PAH losses for a fully dewatered condition would not exceed effluent losses.




Fine-grained Sediments


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Coastal Protection


Book Description

With today's problems surrounding shoreline protection, this book should be of great assistance. This manual contains a compilation of 2 Navy and 2 Corps manuals all relative to the subject of coastal protection and the affects tidal action has on our shorelines. The titles included are: Coastal Protection is a U.S. Navy publication which deals specifically with waves and their characteristics. In order to prepare safe designs, the normal and extreme waves which will act against the structure must be evaluated so that a design wave can be selected. Pilebuck takes the user through this phase into the application of data to actual design of breakwaters and seawalls. Storm Surge Analysis: High tides and wind-generated waves combine to provide a potential for abnormally high water levels and flooding during hurricanes or other serious storms. An understanding of this phenomena is essential in order to plan control structures or design others.




Handbook of Dredging Engineering


Book Description

Authoritative, up-to-date guide to dredging theory and practice. From selecting the right equipment, to evaluating environmental impact, to bidding on a project, Handbook of Dredging Engineering, Second Edition, is the last word on modern hydraulic dredging. Edited by John B. Herbich, with contributions by well-know experts in the field, the Handbook examines basic fluid mechanics; dredge pumps; dredging equipment; sediment; pipeline transport of solids; dredging methods; disposal and placement of dredged material; numerical models for predicting the fate of dredged material placed in open water; environmental effects of dredging activities; instrumentation and automation; and project planning. This vital new edition covers major advances made over the last seven years. Three chapters are new to this edition: numerical models for predicting the fate of dredged material...subaqueous capping of contaminated sediment...and removal of contaminated sediments by dredging, with illustrative case studies.