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    <title>Transport Research International Documentation (TRID)</title>
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    <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>
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      <title>Transport Research International Documentation (TRID)</title>
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    <item>
      <title>DEVELOPMENT OF THE CONCRETE HULL</title>
      <link>https://trid.trb.org/View/69272</link>
      <description><![CDATA[The Author traces the history and development of ferrocement and of reinforced and prestressed concrete as hull materials for a wide range of floating structures.  The distinct characteristics of shipbuilding concrete in terms of materials properties, design, construction techniques, hull shape, size, and weight are critically examined in relation to cargoes carried, special uses, and short and long term operational behaviour.  Experience of concrete hulls indicates two major areas for closer examination and caution in design--impact behavior and weight.  Impact resistance can be improved at extra cost, but the naval architect must move to shapes more able to resist the complex stresses at sea and use higher strength and lower density concrete, if concrete ships are to compete operationally with steel vessels.  An extensive list of references in included. Order from: BSRA as No. 47,918.]]></description>
      <pubDate>Thu, 31 May 2001 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/69272</guid>
    </item>
    <item>
      <title>RE-EVALUATION OF THE PLANING HULL FORM</title>
      <link>https://trid.trb.org/View/154965</link>
      <description><![CDATA[This paper defines the planing hull form, presents a brief historical evolution of the craft, summarizes the recently develpoed technology and its impact upon design and application, and, finally, discusses the potential of the craft.  The authors demonstrate the inappropriateness of stereotyping planing craft as small underpowered boats which must struggle to "get over the hump" and then subject the structure and personnel to severe pounding, wetness, and discomfort when operating in a seaway.  It is shown that, by appropriate application of recently developed technology, planing forms have evolved which are devoid of "hump" problems, demonstrate excellent behavior in a seaway, have substantially useful load fractions, and have a potential growth up to displacements of nearly 1000 tons.]]></description>
      <pubDate>Tue, 16 Sep 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/154965</guid>
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      <title>GROSS ENERGY REQUIREMENTS OF MARINE TRANSPORT</title>
      <link>https://trid.trb.org/View/150143</link>
      <description><![CDATA[Detailed information is required for planning transport systems.  Such information should indicate how different modes and designs use energy, e.g. by comparing hovercraft with conventional ferries, fixed-wing aircraft with helicopters, etc.  The aim of this report is to provide this data by identifying and estimating the major direct and indirect energy requirements of common types of ships.  The methods used to obtain such information are explained along with the assumptions made, as well as the variation of g.e.r. with ship size, speed etc.  The unit of account used is the Gross Energy Requirement (G.E.R.) which is "the amount of energy source sequestered by the process of making a good, or providing a service."  In calculating G.E.R. values five distinct components are identified.  The fuel or direct energy requirement is the most important input to the g.e.r. and consists of the total energy used to provide motive power.  This item is expressed in units of KWht/cargo-ton-mile or KWht/seat-mile (UK long ton and standard mile).  The construction and maintenance energy requirements (e.r.'s), which are indirect energy inputs, are presented in the same units.  The remaining components are less obvious and consist of the energy required to provide transport networks, i.e.  waterways, canals, etc., and fixed facilities such as ports and terminals.  The network energy requirement is expressed in KWht/ton-mile (or KWht/passenger-mile) after the energy input has been partitioned between users.  The fixed facility e.r. must also be partitioned but since no distance factor is incurred by the use of terminals etc., these values are presented in terms of KWht/ton (or KWht/passenger).  Due to this difference with the previous components, the gross energy requirement of a particular system (which is the sum of the individual components) must be expressed in KWht/ton or KWht/passenger for a given voyage.  The study analyzes the four major inputs to marine transport - fuel consumption at sea, construction, maintenance and cargo handling for tankers and dry bulk carriers, general cargo vessels, passenger vessels and short sea or mixed cargo vessels.]]></description>
      <pubDate>Wed, 27 Aug 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/150143</guid>
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    <item>
      <title>INTEGRATED SHIP MACHINERY SYSTEMS WHICH RESULT IN SMALL, EFFICIENT DESTROYERS</title>
      <link>https://trid.trb.org/View/154057</link>
      <description><![CDATA[The use of properly selected integrated ship machinery systems can sharply reduce the size, installed power, and fuel consumption of future Destroyers without reducing payload, speed, range, margins, or stability.  One properly chosen subsystem opens the way to using a second superior subsystem, thus a third one, et cetra, forming a sort of beneficient chain reaction.  The superior subsystems themselves provide highly leveraged effects on the displacement of the ship.  Synergism of this entire chain can result in ships with markedly reduced initial and operating costs.  The most essential elements of this system are: aircraft derivative gas turbines; compact, lightweight electric transmissions; large battery energy storage systems; and contrarotating propellers.  Adoption of these systems permit secondary high-leverage subsystems to be used, including efficient ship service power from propulsion turbines and light-weight maintainable propulsion pods. These changes make total ship rearrangement possible, resulting in major decreases in turbine ducting, propulsion shafting, electric power distribution, and propulsion auxiliaries.  Similar benefits in the auxiliary machinery system result from adoption of reverse-osmosis fresh water production, heat pumps for space heating, glass-reinforced plastic piping, controllable-speed, high-efficiency pump motors, et cetera.]]></description>
      <pubDate>Thu, 26 Jun 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/154057</guid>
    </item>
    <item>
      <title>AN EVALUATION OF ENERGY CONSERVATION APPROACHES FOR SURFACE SHIPS</title>
      <link>https://trid.trb.org/View/154055</link>
      <description><![CDATA[Lower Fleet operating costs and independence from foreign fossil fuel resources are the goals of energy conservation efforts for Navy surface ships.  This paper describes an evaluation of a wide variety of energy conservation approaches.  A standard 20-knot, 300-hour Destroyer mission is established so that all of the approaches can be compared on a total fuel required basis.  The approaches studied include use of aluminum hull construction; light weight machinery; tail-shaft or cross-connect operation for twin screw ships; improved performance propulsors; advanced power plant types, such as COGAS or cruise engines; use of energy storage techniques to improve ship service generator performance; electrical load reductions; improved performance ship service generators; hull drag reductions; crew size reductions; design margin reduction; reduced performance requirement (such as top speed);  and habitability standard reductions.  The overall results can be effected by reductions in range requirements as well. Mission duration was held constant at 45 days throughout the study.  The results of the study indicate that the combination of these various possible improvements may reduce the fuel used to be as low as one-third of the current levels.  Weight reductions are very effective for achieving significant fuel savings.]]></description>
      <pubDate>Thu, 26 Jun 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/154055</guid>
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    <item>
      <title>A UNIFIED APPROACH TO STRUCTURAL WEIGHT MINIMIZATION</title>
      <link>https://trid.trb.org/View/148181</link>
      <description><![CDATA[In this paper the structural sysnthesis problem is limited to the weight minimization of a finite element model of fixed geometry.  The transverse sizes of the elements are the design variables (bar sections, plate thicknesses etc.) in terms of which the structural weight is a linear objective function.  The constraints impose upper bounds on the stresses and the displacements under a set of statical loading cases.  In addition, the so-called technological or side constraints place lower limits on the design variables. Other constraints concerning buckling, dynamic properties etc. can be introduced but are not essential for the present discussion.  In the last decade essentially two main approaches have been used to solve this optimization problem.  One is based on the techniques of mathematical programming (MP), and the other relies on the concept of optimality criteria (OC).  Until recently these approaches were considered as unrelated, and even opposed, to each other.  The purpose of this paper is to show that, far from being opposed, the two classical MP and OC approaches have in fact converged to the same method that consists of transforming the original problem to a sequence of simple, explicit, approximate problems.  Such a method is quite efficient and can be viewed as a generalized OC approach as well as a MP linerization method.  The unified approach presented in this paper yields a new way of finding sound, efficient and consistent OC.  Furthermore, it allows us to understand and control the convergence properties of the optimization process and derive a method lying between a pure OC approach and a primal MP method.]]></description>
      <pubDate>Tue, 22 Apr 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/148181</guid>
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      <title>MARGINAL COST FACTORS FOR HIGH PERFORMANCE SHIPS AND THEIR IMPACT ON SUBSYSTEM DESIGN</title>
      <link>https://trid.trb.org/View/148632</link>
      <description><![CDATA[Investigation reveals that major weapon, propulsion, and sensor subsystems, selected for use aboard Naval vessels, are designed many years prior to the development of a ship. The tendency, by Ship Acquisition Managers, to select off-the-shelf equipment is the result of various political pressures and a requirement to minimize the technical risk of the total ship system.  Subsystem Designers develop their product without regard for the subsystem's impact on possible future ship designs.  The physical characteristics (i.e. weight, required manning, electrical power, and space required) of a subsystem are not controlled and the growth of these parameters is a major factor in the escalating cost of Naval ships.  To assist both the Ship and the Subsystem Acquisition Managers/Designers in controlling costs, Marginal Cost Factors are proposed.  Previous work has demonstrated the validity of the concept of Marginal Factors to predict the ship-growth costs due to the impact of subsystems on conventional displacement ships.  This thesis builds upon this work by using two ship synthesis computer models to generate Marginal Weight Factors for two high performance ship types of recent interest to the U.S. Navy - Hydrofoils and Surface Effect Ships.  (Author)]]></description>
      <pubDate>Mon, 31 Mar 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/148632</guid>
    </item>
    <item>
      <title>OPTIMISATION OF THE HULL OF CARGO SHIPS</title>
      <link>https://trid.trb.org/View/87426</link>
      <description><![CDATA[Two optimisation programs described in this study are based on a dynamic calculation model of digital variables and have been used for hull optimisation of a 5,000 dwt cargo ship, a 38,000 dwt bulk-carrier, and a 100,009 dwt tanker using the parameters of weight and cost.  Practical application of the programs in design of new ships has resulted in 2-8% savings in hull weight.  Order from BSRA as No. 49,569.]]></description>
      <pubDate>Tue, 31 Jul 1979 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/87426</guid>
    </item>
    <item>
      <title>STRUCTURAL DESIGN STUDY OF A HIGH LENGTH-TO-BEAM RATIO SURFACE EFFECT SHIP</title>
      <link>https://trid.trb.org/View/85470</link>
      <description><![CDATA[Parametric studies are performed to determine the effect on structural weight fraction of (1) varying loading conditions and (2) varying material strength.  It has been found that the structural weight fraction of the 4000-ton surface effect ship (SES) is sensitive to longitudinal bending, torsion, and pressure loads in descending order, in contrast to the smaller "ses" when pressure loadings dominate the design.  Order from NSFI as No. 16342.]]></description>
      <pubDate>Wed, 25 Apr 1979 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/85470</guid>
    </item>
    <item>
      <title>THE COST OF IRRATIONALITY IN SHIP STRUCTURE DESIGN</title>
      <link>https://trid.trb.org/View/85444</link>
      <description><![CDATA[The main factors affecting the rationalization of ship structural design are analysed.  Particular emphasis is placed on those factors affecting hull steel weight.  The loss of income resulting from undue increase in hull steel weight, deficient hull girder stiffness, poor design of local structural connections and complex constructional arrangements is examined and evaluated.  It is shown that irrational design of ship's structure may have adverse economical consequences to both shipbuilder and shipowner.]]></description>
      <pubDate>Wed, 28 Mar 1979 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/85444</guid>
    </item>
    <item>
      <title>STUDY ON APPLICATION OF STATISTICAL TREATMENT TO ESTIMATION OF FUNDAMENTAL QUANTITIES (OF HULL STEEL, ETC.) AT INITIAL DESIGN STAGE</title>
      <link>https://trid.trb.org/View/72707</link>
      <description><![CDATA[The estimating of quantities such as hull steel weight, pipe weight, painted area, etc. at the initial design stage of a ship is very important, but at that stage, when the design has not been developed in detail, it is difficult to calculate such estimates even with the help of previous experience.  The Authors describe the investigation of the possibility of obtaining the estimates by statistical analysis.  This method was found to be of practical value in selecting variables and simplifying the estimation work. Order from: BSRA No. 47,641.]]></description>
      <pubDate>Wed, 26 Apr 1978 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/72707</guid>
    </item>
    <item>
      <title>SOME SHIP DESIGN METHODS</title>
      <link>https://trid.trb.org/View/60661</link>
      <description><![CDATA[This paper was presented on 9 Nov. 1976 in Glasgow at a joint meeting of the RINA and the IEES, and on 24 Nov. 1976 at an RINA meeting in London.  The discussions following both presentations are included in the paper, together with a written Discussion and the Authors' replies to all three. Since the publication, in 1962, of the first-named Author's paper "Estimating Preliminary Dimensions in Ship Design", there have almost certainly been greater changes in ships than during any previous period of this length.  The Authors (of Y-ARD Ltd) review these changes, examine the present relevance of the design data and methods presented in 1962, discuss developments in ship-design methods since that date, and consider the present state-of-the-art of preliminary design.  The paper is arranged under the headings:--1) Introduction (Changes in Ships and the Shipping Fleet--The Changes in Machinery--Design Starting Point--Design Methods). 2) The Three Ship-Design Categories (The Deadweight Carrier--The Capacity Carrier--The Linear Dimension Ship--Solution of cubic Equations).  3) Dimensions, Displacement and Form (The Dimensional Relation-ships--The Beam/Length Relationship B=f(L)--Depth/Beam Relationship D=f(B)--The Draught/Depth Relationship T=f(D)--The Depth/Length Relationship D=f(L)--The Draught/Length Relationship T=f(L)--The Draught/Beam Relationship T=f(B)--Block Coefficient--Displacement--Appendages--Longitudinal Centre of Buoyancy).  4) Powering (Effective Horsepower PE--Adoption of ITTC Notation--Appendage Resistance--Correlation Factors--Quasi Propulsion Coefficient--Transmission Efficiency--Trail and Service Margins--Engine De-Rating).  5) Lightship Weight (Steelweight Ws--Scrap--Outfit Weight--Machinery Weight--Margin). See also MRIS Abstract 168254. Order from: BSRA as No. 47,080.]]></description>
      <pubDate>Mon, 30 Jan 1978 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/60661</guid>
    </item>
    <item>
      <title>COST-WEIGHT OPTIMIZATION OF NON-STEEL MIDSHIP SECTIONS</title>
      <link>https://trid.trb.org/View/33550</link>
      <description><![CDATA[This material presents a procedure, which may be automated, for determining the least-weight and associated cost of midship hull structure composed of one or more isotropic, homogeneous materials.  The procedure is founded on an existing procedure for design with steels which has been proven viable.  The procedure designs plates and stiffeners using classical relations and the actual properties of the materials.  For computing the section modulus of the hull, equivalent steel plate thicknesses and stiffener transverse dimensions, determined from a ratio of elastic moduli, are used.  This is done even if no steel exists in a design. Transverse members are designed to a required steel section modulus.  If a member is other than steel, the required section modulus becomes that of steel times a ratio of material strengths.  An automated procedure of this material has been partially developed and is on file with the Department of Ocean Engineering at M.I.T.  A detailed documentation of the automated procedure is not here presented, but, hopefully, will be forthcoming.  The procedure was developed with aluminum in mind and a survey of its properties and qualities is included.]]></description>
      <pubDate>Sat, 18 Oct 1975 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/33550</guid>
    </item>
    <item>
      <title>OPTIMISING HULL STEEL WEIGHT FOR OVERALL ECONOMIC TRANSPORTATION</title>
      <link>https://trid.trb.org/View/39732</link>
      <description><![CDATA[The structural design of a ship has a direct influence on her operation, safety and economy of transportation. Therefore, the design procedure should be rationalized with particular emphasis on structural safety and optimization. A ship should have adequate strength to resist the loads imposed by the hostile sea environment and at the same time she should have the lightest possible steel structure. Ship structure optimization thus becomes an essential part of the design process.  This article outlines the economic consequences of structural optimization and provides a criterion for the determination of the optimum hull steel weight.  It also emphasis the need for data collection on structural failures and associated costs and delays. (Author)]]></description>
      <pubDate>Thu, 24 Jul 1975 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/39732</guid>
    </item>
    <item>
      <title>A CONTRIBUTION TO THE DETERMINATION OF THE STEEL HULL WEIGHT OF DRY CARGO SHIPS</title>
      <link>https://trid.trb.org/View/20853</link>
      <description><![CDATA[A new method for the calculation of the steel weight of dry cargo ships has been developed under sponsorship of Germanic Lloyd and the German Research Association.  This method is based on the regulations of Germanic Lloyd; it is intended to complement, not replace, existing methods. Since it deals only with the total steel hull weight and its vertical center of gravity, the new method cannot replace current methods that also serve to calculate other weight groups.  Furthermore the applicability of the new method is limited to dry cargo ships.  The aim of this paper is to examine accurately, according to the latest state of the art, the relationship between steel weight and the main design characteristics of the hull.]]></description>
      <pubDate>Tue, 31 Dec 1974 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/20853</guid>
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