<rss version="2.0" xmlns:atom="https://www.w3.org/2005/Atom">
  <channel>
    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
    <description></description>
    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
    </image>
    <item>
      <title>A MATHEMATICAL MODEL FOR CALCULATING CURRENT-INDUCED LOADS ON MOORED VESSELS USING FREE-STREAMLINE AND STRIP THEORIES</title>
      <link>https://trid.trb.org/View/393045</link>
      <description><![CDATA[This report details a mathematical model for calculating the steady forces and yaw moment on a moored vessel induced by an incident current from any oblique angle. For oblique flows, the lateral forces and yaw moment are modelled using a free-streamline strip theory which accommodates arbitrary mono-hull shapes, end effects, finite water depths, horizontally and vertically sheared current profiles, and wave radiation effects. For near head-on and beam-on flows, the longitudinal force is modelled using conventional ship resistance and low aspect ratio airfoil relationships. (Author)]]></description>
      <pubDate>Mon, 21 Jul 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/393045</guid>
    </item>
    <item>
      <title>USING WIND, WAVE AND CURRENT TIME HISTORIES TO ESTIMATE REALISTIC EXTREME JOINT LOADING CONDITIONS</title>
      <link>https://trid.trb.org/View/455356</link>
      <description><![CDATA[The paper describes an environmental monitoring program in place on the North Alwyn platform operated by Total Oil Marine in the northern North Sea.  It uses an intelligent data-logging system to record the wave, wind and current conditions at a high sampling rate. For storm conditions the raw data is saved and under calmer conditions, all wave height/wave period pairs are stored along with summary wind and current conditions for use in fatigue studies and long term probability models.  Analysis of the time histories is aimed at the time-domain correlation of the directional loading constituents to give a more realistic extreme loading envelope than is possible from gross summary statistics.  A joint probability model is also being developed for wave, wind and current conditions.  Illustrative examples of temporal and directional discrepancies between maxima of wind and wave traces are presented to provide a comparison with the more common assumption that the worst overall conditions is represented by the simultaneous occurrence of the worst case of each of the environmental loading factors.]]></description>
      <pubDate>Mon, 04 Mar 1996 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/455356</guid>
    </item>
    <item>
      <title>SMALL-SCALE TESTING ON CURRENT-INDUCED FORCES ON A MOORED TANKER</title>
      <link>https://trid.trb.org/View/450343</link>
      <description><![CDATA[Tankers and barges are often moored in high current in restricted channels.  The design of the mooring lines requires the accurate knowledge of the current forces on these vessels.  Tests were conducted on a tanker model in current produced in shallow and deep water.  Current generated in the test tank had both uniform and linear shear profiles.  The shear was positive as well as negative.  The angle of the tanker to the current direction was varied and the inline and transverse forces on the tanker were measured with load cells placed in the mooring lines.  Extensive data is presented on the lateral force coefficients on the tanker model. Deviation of the results from the OCIMF data is discussed.]]></description>
      <pubDate>Mon, 14 Aug 1995 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/450343</guid>
    </item>
    <item>
      <title>MOTION SIMULATION AND DYNAMIC STABILITY OF AN ANCHORED TANKER SUBJECT TO CURRENT, WIND AND WAVES</title>
      <link>https://trid.trb.org/View/436319</link>
      <description><![CDATA[motions and anchor chain forces of a supertanker when anchored in a steady current, with or without wind and waves, were simulated. Additionally, locally linearised stability analysis of equilibrium states were carried out. Five sets of forces were modelled: 1) nonlinear quasi-steady hydrodynamic response and control forces based no a four-quadrant manoeuvring model, 2) linear memory effects due to radiated waves, 3) nonlinear anchor chain force, 4) variable wind forces and 5) first-order forces and drift forces due to waves. Current speed, wind speed, significant wave height, hawsepipe location, anchor chain length and rudder deflection were varied systematically. Results are presented as stability domains in parameter space for constant wind forces and wave drift forces and confirmed by complementary simulations. Selected simulations were also performed in variable wind and irregular waves. Three practical measures to stabilise vessel motions and to reduce tensile force peaks in the anchor chain were examined: selective use of either port or starboard hawsepipe, rudder deflection and choice of anchor chain length.]]></description>
      <pubDate>Mon, 14 Aug 1995 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/436319</guid>
    </item>
    <item>
      <title>CURRENTS AND WAVE FORCES ON SHIPS AND MARINE STRUCTURES</title>
      <link>https://trid.trb.org/View/440060</link>
      <description><![CDATA[Forces on a body oscillating in incoming waves and a weak current are studied.  Coupling between the oscillatory wave field and the steady flow around the body is accounted for.  Friction and separation effects are disregarded, and the fluid flow is modelled by potential theory.  The boundary value problem for the velocity potential is transformed to an integral equation by Green's theorem, using a Green function satisfying the linear free surface condition with small forward speed.  Local, small forward speed expansions for the potential and the Green function are applied in the vicinity of the body, giving two sets of integral equations for the unknown zero speed and the small forward speed potentials.  There are unknowns on the wetted body surface only.  The right hand side of the small forward speed integral equation involves a fast decaying integral over the free surface.  There is no water line integral in the integral equations.  The method is applicable to bodies of arbitrary shape.  The diagonal added mass and damping coefficients are found to be functions of the current speed only through the encounter frequency.  The linear exciting forces are found by generalised Haskind relations.  Analytical expressions for the mean second order horizontal drift forces and the mean second order yaw moment are given, and numerical examples are presented for different body geometries.  The mean drift forces are usually increased by the presence of a weak current along the incoming wave direction.  For complex body geometries the wave drift damping may, however, in narrow wave number regions, become negative.  The mean yaw moment may be changed by 100% by the presence of a weak current.  Energy check and numerical convergence of the method are also discussed.]]></description>
      <pubDate>Mon, 14 Aug 1995 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/440060</guid>
    </item>
    <item>
      <title>EFFECT OF CURRENT AND WAVES ON THE DAMPING COEFFICIENT OF A MOORED TANKER</title>
      <link>https://trid.trb.org/View/402421</link>
      <description><![CDATA[It is described how a model test was performed on a 67,000 dwt tanker moored in head seas fore and aft with linear springs, in combinations of regular waves and current. At the initiation of each test run, the vessel was displaced and released from its equilibrium position. The resulting motions and line loads were recorded. The data was analyzed to determine the effects of wave amplitude and frequency, as well as that of the current, on the damping factor and the added mass coefficient. The first order responses and steady drift loads resulting from the regular waves are also presented.]]></description>
      <pubDate>Thu, 21 Jul 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/402421</guid>
    </item>
    <item>
      <title>CURRENT-INDUCED VESSEL FORCES AND YAW MOMENTS FROM FULL-SCALE MEASUREMENTS</title>
      <link>https://trid.trb.org/View/392624</link>
      <description><![CDATA[Full-scale measurements of the current-induced forces and yaw moments on a T-2 tanker and Spruance class destroyer are presented. The T-2 data set is made up of 23 tests, including water depth-to- draft ratios between 2.5 and 6, incident current angles between 0 and 95 degrees, current speeds up to 4 ft/sec, and horizontal and vertical current shears. Results are presented from 14 tests of head-on and beam-on loads on a Spruance class destroyer. The deep water lateral force coefficient is shown to be independent of hull shape but with a magnitude that varies 50% depending on the vertical current shear. Analysis of the deep water longitudinal force, the shallow water lateral force, and the yaw moments shows that these coefficients do not follow "accepted" patterns. These data provide a unique and reliable data set for validating current load methodologies and for validating similitude relationships for small-scale mooring and maneuvering studies.]]></description>
      <pubDate>Thu, 21 Jul 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/392624</guid>
    </item>
    <item>
      <title>AN ASSESSMENT OF STATE-OF-THE-ART METHODS FOR CALCULATING CURRENT LOADS ON MOORED SHIPS</title>
      <link>https://trid.trb.org/View/392393</link>
      <description><![CDATA[This report presents an examination of techniques for computing current-induced forces and yaw moment on moored vessels based on experimental data or procedures from nine independent sources. No validated full-scale data were located, so only relative evaluations were possible. For the lateral and longitudinal current forces, the nine sources were applied directly (or scaled) to two representative hull types. This comparison shows extreme differences among the nine methods.  It is concluded, based on these differences that the present uncertainty in these state-of-the-art current force predictive methods is + or - 80% for head currents (longitudinal force) and + or - 50% for beam currents (lateral force). Comparisons are also presented for the current-induced yaw moment and water depth (blockage) correction factor. The differences among these latter two are even greater than those for the lateral and longitudinal forces. The Navy's DM-26 approach was found to be inconsistent and can be in error by a factor of 5; the latest draft (90%) of the ongoing revision of that manual (DM 216.6) was considered acceptable except for the longitudinal forces. Because of uncertainties in the scaling criteria, full-scale measurements are recommended to allow proper evaluation of these various methods. (Author)]]></description>
      <pubDate>Thu, 21 Jul 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/392393</guid>
    </item>
    <item>
      <title>EFFECT OF CURRENT DRAG FORCES ON TWO LARGE BODIES IN CLOSE PROXIMITY</title>
      <link>https://trid.trb.org/View/402422</link>
      <description><![CDATA[Two large bulk carriers were intended to be used in an iron ore transshipment project for offshore operation in Venezuela. On site in normal operating conditions, the export ship had to approach the permanently spread-moored transfer station and berth alongside without the assistance of tug boats. The loading site was located near an estuary with a year-round current having a maximum velocity of two knots. The berthing arrangement enabled the export ship to be sheltered and protected by the transfer station. The current direction was at 67.5 degrees from the centerline of the transfer station, toward the starboard side of the vessel. No analytical or model test data was available to examine the effect of current drag forces on two large bodies in close proximity. As a worst case scenario, model tests were conducted with current coming at 90 degrees toward the starboard side of the transfer station. A combination of draft conditions and hull separations was considered to examine the current force and yaw moment on the vessels.  With the two ship models arranged to be tested at different draft and separation combinations, results clearly indicated the change in behavior of side force and yaw moment due to boundary layer effect as a result of close proximity. The distorted flow along the sides created a pulling force between the two hulls when the models were set at the minimum separation of 10 feet prototype apart. Tests were also conducted with a single model in the basin. Results were in close agreement to calculations using prediction methods of Oil Companies International Marine Forum (OCIMF). Physical modeling of large bodies in close proximity provides useful information to ship operators for offshore transfer of cargo from one ship to another, in terms of hawser loads and fendering loads.]]></description>
      <pubDate>Thu, 21 Jul 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/402422</guid>
    </item>
  </channel>
</rss>