Criteria for the Depths of Dredged Navigational Channels (1983) / Chapter Skim
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Appendix A: Abstracts of Pertinent Articles and Reports
Appendix A: Abstracts of Pertinent Articles and Reports
Pages 115-144
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From page 115... ...
, "Major Port Improvement Alternatives for the Texas Coast," COE Report No. 197, TAMU-SG-77-205 (College Station, Tex.: Texas Ash University)
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From page 116... ...
, "A Mathematical Model for the Review or Design of Deep-Draft Navigation Channels with Respect to Vessel Drift and Rudder Angles," Proc.
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From page 117... ...
, "Prediction of Shoaling Rates in Offshore Navigation Channels," Center for Dredging Studies, Department of Civil Engineering, Report No. 232 (College Station, Tex.: Texas A&M Uniters ity ~ .
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From page 118... ...
( 1980 ) , "Full-Scale Measurements and Statistical Analyses of Ship Motions in a Navigational Channel, n Marine Tech., 17: 351-370 .
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From page 119... ...
Author's Abstract The report contains four papers on squat in shallow water as follows: from the Federal Republic of Germany, a paper on the results of model tests of a 700,000 DWT tanker; from France, a paper on the results of model tests of a 500,000 DWT twin-screw tanker; from Poland, a paper on the results of model tests of two ships with large block coefficients, one with bulbous bowl and from the United Kingdom, a paper on the results of model tests of two ships, one in the naked hull condition, and the other equipped with self -propulsion gear, twin screws, twin rudders, and bulbous bow. Anonymous (1979)
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From page 120... ...
, "Major Port Improvement Alternatives for the Texas Coast, " COE Report No. 197, TAlIIJ-SG-77-205 (College Station, Tex.: Texas A&61 University)
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From page 121... ...
The port improvements for the Texas coast are deemed to be necessary to provide modern and efficient port facilities to shippers and ensure continued economic well-being for the regions served by these ports. Ship channel design criteria are discussed in terms of mi nimbi width and depth requirements for various size vessels.
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From page 122... ...
251 (Netherlands: Delft Hydraulics Laboratory ~ . Abstract This paper presents a harbor design strategy in which the nautical aspects are treated as an integral part.
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From page 123... ...
Standard maneuvers such as the zig zag, spiral, or sine test are used to determine the reaction of the vessel in full-scale, deepwater trials or in hydraulic model tests in the laboratory. Another index used by naval architects to define controllability is the tu~ning.circle at full ahead speed with a 35° starboard rudde '..
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From page 124... ...
The bank suction module computes the lateral forces and turning moments due to the bank suction phenomenon. The neutral steering line module computes the distance between the neutral steering line and the channel centerline for a given cross-section and then adds this distance algebraically to the given ship off-centerline distance.
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From page 125... ...
The mathematical model and related theory described in this document provide the engineer with a comprehensive tool in the design and review of deep-draft navigation channels. Through its use he will be able to predict values of squat, bank suction forces and moments, equilibrium drif t and rudder angles, and heights of ship~generated wares for varied channel configurations, ship positions and ship velocities.
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From page 126... ...
A (1979~, "Density Measurements in Situ" (Netherlands: Public Works Department, Lower Reaches Directorate, Measuring Division, Research Sections.
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From page 127... ...
Army Engineer Waterways Experiment Station (WES) has undertaken a study to determine the minimum dimensions of deep-draft navigation channels compatible with the assurance of safe operating conditions.
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From page 128... ...
~ , _~ International Association of Ports and Harbors (1981) , "Special Care Measures for Safe Disposal of Polluted Dredged Material in the Marine Environment," Submitted to the Ad Hoc Scientific Group on Dumping -- 5th Meeting, Halifax, Canada, May 4-8.
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From page 129... ...
, "Definition of the Seabed in Navigation Routes through Mud Areas," International Hydrographies Rev., Monaco, LVII (1~: 107-117 (Also First International Hydrographic Technical Conference, Ottawa, May 1979~. Author's Abstract Over most types of seabed the interface between the seabed sediment and the overlying sea water column is sharp and clearly identified by ~ -- ~ large mobile survey echo sounders.
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From page 130... ...
The controllability of a ship in open and in confined water is affected by the vessel' s characteristics and speed, winds, waves, currents, visibility, solid obstructions, shoaling, and traffic. The vessel behavior in channels and maneuvering areas is influenced by bottom and bank suction, interference of passing ships, rudder response, and increase in required driving power in shallow, confined waters.
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From page 131... ...
, "Sedimentation in Dredged Navigation Channels," Proc. 17th Coastal Eng.
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From page 132... ...
Two alternative entrances were studied, and in conclusion it was recommended to improve the existing access channel through Escravos Entrance, as this solution would yield much smaller maintenance dredging quantities as compared to an access channel through Forcados Entrance. In 1978, it was decided to improve the accuracy of the sedimentation estimates for a dredged channel through Forcado" Entrance, and therefore it was recommended by DHI to dredge test pits in the alignment of the channel and to carry out a pertinent monitoring program.
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From page 133... ...
Over the next five years, that volume is expected to double. The existing channel depth in the Hampton Roads is 45 ft.
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From page 134... ...
The study was part of a joint research project entitled "Minimization of the Cost of Maintenance Dredging" and has given birth to different ideas about the required depths of ports and rivers . This is of interest to nautical experts because it has extended the "available water depth" notion which from now on should be judged somewhat differently insofar as muddy beds are concerned.
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From page 135... ...
This paper presents an empirical method of shoaling analysis based on historical dredging and shoaling records that results in reliable predictions of future shoaling for deepened channel conditions occurring either from an increase in authorized channel depth or from The method presented was designed to be general enough that it can be applied to most navigation projects without difficulty. - ~ ~ ~ ' ' ~ , advance maintenance.
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From page 136... ...
The dredging requirements of six selected entrance channels for both the existing dimensions and the immediately previous dimensions were determined to evaluate the "volume of cut" prediction technique. The six projects, selected on the basis of availability of historical dredging data, were the Wilmington Harbor entrance channel in North Carolina, the Pascagoula Harbor entrance channel in Mississippi, the Calcasieu River entrance channel in Louisiana, the Sabine-Neches entrance channel and the Galveston Harbor entrance channel in Texas, and the Yaquina Bay and Harbor channel in Oregon.
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From page 137... ...
Army Engineer Waterways Experiment Station (WES) is conducting a study to determine the minimum dimensions of deep-draft navigation channels for safe and efficient navigation.
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From page 138... ...
This paper describes the technical aspects of both of these methods. The advantages of bucket dredgers are discussed, and the increased production obtained after introduction of density measurement instruments for determining nautical depth is outlined.
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From page 139... ...
The discussion includes the siltation process and the concept of nautical depth in a soft-bedded channel. A comparison of the advantages and disadvantages of density measuring probes and echo sounders is presented.
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From page 140... ...
Is a result of-~he ine-ff~c~ency of con vend; maintenance -dredging other alternatives may be adopted to decrease the dredging requirement. Examples discussed are the location of port facilities in zones of low sedimentation or prevention of silt penetration using locks, bubble curtains or removable barriers.
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From page 141... ...
The objective of this study was through measurement and analysis of the vessel motions to validate the design assumptions for a specific channel as well as to establish the general design information on channel width and depth requirements, with respect to the ship characteristics and channel environments. Full-scale measurements of motion characteristics for 29 vessel transits through the Columbia River Entrance Channel have been conducted.
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From page 142... ...
ASCE, _(WW3~: 455-473. ~ Abstract The state-of-the-art in the selection of channel depth is briefly reviewed to emphasize the fact that channel depth design in the United States has been more a matter of judgment than one of rigorous engineering analysis.
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From page 143... ...
ASCE , _ 97 (WvI3 I: 443-4~4. Abstract Me state-of-the-art involved in the design of a ship channel is briefly reviewed to stress the lack of knowledge concerning the channel depths, widths, and all ~ ents necessary for safe navigation.
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From page 144... ...
Human failures can involve a lack of knowledge of the channel inadequacies or the vessel peculiarities, a lack of skill, a tendency to risk-taking, or a lack of complete attention. With increasing vessel size and cost, navigation channels must be deepened and widened, and the designer must be provided with the necessary knowledge to design safe and economic channels.
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