Accession Number : ADA294003
Title : Technologies for Hopper Dredge Production and Process Monitoring. Laboratory and Field Investigations (Dredging Research Program).
Descriptive Note : Final rept.,
Corporate Author : ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS
Personal Author(s) : Scott, Stephen H. ; Jorgeson, Jeffrey D. ; Savage, Monroe B. ; Cox, Cary B.
PDF Url : ADA294003
Report Date : FEB 1995
Pagination or Media Count : 97
Abstract : This Dredging Research Program (DRP) work unit was initiated to investigate methods for monitoring hopper dredge production and operation. Hopper dredging accounts for a significant portion of the total amount of material dredged in the United States. The operating costs for a hopper dredge are significant. The cost may vary from approximately $30,000 to $75,000 per 24 hour day, depending on the size of the dredge and the support requirements. Typically, the cost efficiency of a dredge is judged by its ability to move sediments from the project area to disposal with a minimum of pumping and traveling time. The ideal hopper load for accomplishing this is referred to as the economic load. Better methods are needed to monitor dredge processes which will reveal the optimal operation for achieving the goal of economic load. Under this work unit, two methods were designed, fabricated, tested, and evaluated for effectiveness in providing data to dredge personnel for the purpose of increasing dredge efficiency. A resistivity probe was developed to directly measure the vertical density profile of dredged material in the hopper. An instrumentation package which included acoustic and pressure sensors was developed to monitor the real time dredge displacement and hopper volume and indirectly measure the density of dredged material in the hopper. The data resulting from the application of both systems can be used for calculating dredge production on a load by load basis. This report presents the description and method of the testing programs and the study findings. The concept of uncertainty analysis for determining the error potential in hopper dredge production calculations is presented and discussed with an example calculation.
Descriptors : *DREDGED MATERIALS, *DREDGING, *SEDIMENTS, DENSITY, PROBES, UNCERTAINTY, UNITED STATES, OPTIMIZATION, COMPUTATIONS, PRODUCTION, COST EFFECTIVENESS, ECONOMICS, REAL TIME, RESISTANCE, DISPLACEMENT, FIELD TESTS, TIME, COSTS, PROFILES, ERRORS, PRESSURE, OPERATION, INSTRUMENTATION, DISPOSAL, ACOUSTIC DETECTORS.
Subject Categories : Civil Engineering
Distribution Statement : APPROVED FOR PUBLIC RELEASE