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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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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>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>Assessing Coating Degradation Along a Scribe in a Ballast Tank Environment</title>
      <link>https://trid.trb.org/View/2676077</link>
      <description><![CDATA[This study evaluates the suitability of corrosion testing methods for analyzing the scribe performance of coated steel in environments resembling ballast tanks. While the fog/dry test effectively accelerates corrosion on bare steel, it falls short of replicating ballast tank conditions for coated scribed steel. it shows significant variability, which limits precise evaluation. a procedure previously developed at AMACORT, the AMACORT CIFD-01 test procedure, proves more reliable for scribe performance analysis, offering greater precision and repeatability. This study also explores the effects of surface cleanliness and roughness on coating performance using the fog/dry test method. Fog/dry testing is used as it is widely recognized and commonly applied, whereas the aMacort cifD-01 protocol requires significantly more handling. increased salt contamination correlates with a greater mean creep, which becomes significant when PSPC₁₅ standards are being exceeded. Regarding dust contamination and surface roughness deviations, no significant effects were observed, like those seen with increased salt contamination. a dust contamination increase contributes to performance degradation but not significantly, nor do surface roughness deviations. these findings underscore the importance of selecting appropriate test methods and maintaining adherence to surface cleanliness and roughness standards, in particular salt contamination, to ensure optimal coating performance and adhesion durability.]]></description>
      <pubDate>Wed, 25 Mar 2026 11:44:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2676077</guid>
    </item>
    <item>
      <title>Optimising liquid level in a spherical two tank interacting system with fractional order PID control via hybrid POA-RERNN approach</title>
      <link>https://trid.trb.org/View/2526735</link>
      <description><![CDATA[This paper proposes a hybrid technique for liquid level in a spherical two tank system. Of the three controllers, the fractional-order internal model controller (FOIMC) was tuned using the proposed fractional-order proportional integral derivative (FOPID) controller in an interacting system (TTSIS). Recalling-enhanced recurrent neural network (RERNN) and pelican optimization algorithm (POA) combined performance is the proposed hybrid technique. The FOPID controller is used to control the system's level. The hybrid approach that has been proposed tunes the FOPID's ideal gain parameter. The proposed method's performance is evaluated using the MATLAB site and contrasted with other methods that are currently in use, such as the whale optimization algorithm (WOA), particle swarm optimization (PSO), and Salp swarm algorithm (SSA). After analyzing the control efforts (errors) and robustness, it is determined that the proposed approach has better robustness than the current methods and requires less control effort overall.]]></description>
      <pubDate>Wed, 19 Nov 2025 17:09:40 GMT</pubDate>
      <guid>https://trid.trb.org/View/2526735</guid>
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    <item>
      <title>Development of Corrosion Wastage Assessment Methodology for Water Ballast Tanks: An Aging Bulk Carrier</title>
      <link>https://trid.trb.org/View/2592112</link>
      <description><![CDATA[Various environmental factors, operating conditions, transport routes, the type of transported cargo, maintenance practices, and other external and internal factors significantly influence the development of corrosion. Cargo holds and water ballast tanks are particularly susceptible to corrosion damage. This study investigates the extent to which steel thickness reduction due to corrosion contributes to the degradation of steel structures and whether this reduction aligns with the adopted Common Structural Rules (CSR). The analysis is based on an aging bulk carrier and three types of ballast tanks within the cargo hold area: top-side tanks, hopper-side tanks, and double-bottom tanks. Thickness measurements were conducted on nine specific transverse structural locations, and a corrosion wastage assessment methodology was developed based on a nonlinear stochastic model. The corrosion growth rate was modeled using a probabilistic approach where the corrosion rate parameter d0 follows a Weibull distribution. The model also incorporates 95% confidence intervals to reflect uncertainty and assess early risk exceedance relative to CSR corrosion margins. The results revealed significant differences in corrosion behavior among ballast tank areas and identified critical zones where corrosion thresholds are reached earlier than expected. The proposed methodology demonstrates its applicability in assessing structural degradation patterns and validating CSR-based corrosion allowances.]]></description>
      <pubDate>Fri, 22 Aug 2025 12:00:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2592112</guid>
    </item>
    <item>
      <title>Corrosion degradation impact on cargo hold main frames of single skin bulk carriers</title>
      <link>https://trid.trb.org/View/2528975</link>
      <description><![CDATA[Damage due to corrosion occurs most often in the form of general corrosion or pitting, although other forms of corrosion such as crevice, microbiological, fretting, etc. can also occur. Damage to structure due to corrosion can be expressed by the loss of metal thickness expressed in mm or percentage of wear, as well as by the loss of metal weight. Corrosion appears at different speeds and in different areas depending on numerous external and internal factors. So far, research has shown that cargo holds, and ballast tanks of bulk carriers are the most susceptible to structural damage due to corrosion. In this paper, the authors analyze the main frames, as part of a cargo hold for transporting bulk cargo. Using the example of ten old single-hull bulk carriers, the authors consider the amount of steel that has been replaced over time. Applying the acceptance criterion prescribed by the classification societies, measurements were made of the main frames and the defined damaged surface of the structure, which needed to be replaced due to excessive corrosion. In this way, the cumulative amounts of damaged steel over time were calculated and expressed in tons of replaced steel. Observing the changes in ships in exploitation in the period from 10 to 30 years of exploitation, the ships were monitored during several special surveys. Calculating the annual amount of replaced steel and fitting the distribution showed that the three-parameter log-logistic distribution gives the best values of weight replacement.]]></description>
      <pubDate>Fri, 20 Jun 2025 11:58:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2528975</guid>
    </item>
    <item>
      <title>The pressure hull collapse and protective cover in high-pressure environments</title>
      <link>https://trid.trb.org/View/2507279</link>
      <description><![CDATA[The pressure-resisting structures on the manned submersible include not only the manned sphere hull but also various pressure-resisting tanks and pressure-resisting equipment. When implosion occurs, the impact energy will be transferred to the adjacent components on the deep-sea submersible, causing great danger to the safety of the deep-sea submersible. In this paper, the adjustable ballast water tank is taken as an example. Pressure hull collapse under a high-pressure environment is simulated. By analysing the calculation results of the three-phase coupling model, it can be obtained that the collapse mode and collapse load in the finite element analysis are in agreement with the experiment. To reduce the impact of pressure hull collapse, the deep-sea explosion-proof device is designed and the wall thickness is calculated. This paper provides a reference for the study of pressure hull collapse and protective cover design in high-pressure environments.]]></description>
      <pubDate>Mon, 24 Feb 2025 12:00:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2507279</guid>
    </item>
    <item>
      <title>Comparison between ballast water sampling skid and traditional ballast water sampling devices: A case study of ship sampling</title>
      <link>https://trid.trb.org/View/2480331</link>
      <description><![CDATA[With the ratification of the International Convention for the Control and Management of Ships' Ballast Water and Sediments in 2004, assessing the compliance of ships with ballast water discharge standards has become imperative. To facilitate this task, a sampling skid was developed to collect ballast water samples efficiently in the confined space of a ship. This study compared the sampling performance of the sampling skid, conventional ballast water sampling devices (e.g., manholes and sounding pipes), and sampling devices for ballast water discharge pipelines (zooplankton nets) over three biological size ranges: >=50 mcm, >=10 mcm to <50 mcm and <10 mcm. The results showed no significant differences between the sampling skid and other sampling devices in these size ranges. When continuous sampling was performed, biological data obtained by the sampling skid were more stable than those obtained by conventional ballast water sampling devices. Furthermore, the utilization of a sampling skid ensured a stable sampling flow rate and reduced sampling time compared to similar sampling methods. The potential impact of the performance of this sampling equipment on different vessel types and sampling environments should be explored more thoroughly in future work.]]></description>
      <pubDate>Mon, 30 Dec 2024 15:51:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2480331</guid>
    </item>
    <item>
      <title>Coating Condition Monitoring and the Practical Application</title>
      <link>https://trid.trb.org/View/1974311</link>
      <description><![CDATA[Corrosion is a main source of degradation of most offshore and ship structures. Especially ballast tanks are vulnerable to corrosion. Protection is provided by coating systems, postponing the onset of uniform corrosion. It is therefore essential to have a coating system in place and intact. Inspecting ballast tanks for the integrity of the coating system is an operational challenge. The improvement is to detect coating degradation before the corrosion process starts and only enter when it is required.Within the European project SAFEPEC [1], it has been reported that continuous inspection of the condition of the coating system helps improving the reliability of the structure. Hoogeland et al. [3] described a coating condition monitoring system that uses electrochemical measurements, i.e. the electrical current between steel to be protected and an anode. This paper demonstrates the reliability of the monitoring system by experimental validation using a Bayesian approach.A long term measurement campaign has been performed on board a vessel. Inside a ballast tank, specimens are attached and intermittently exposed to seawater. The electrical current between these plates and the anode are measured over about two years. The measurements are analyzed and based on the results, the condition of the coating of the installed specimens is predicted. By showing the actual status of the specimens, the reliability of the system is shown and the applicability for wider use is explained.]]></description>
      <pubDate>Fri, 23 Aug 2024 16:53:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974311</guid>
    </item>
    <item>
      <title>Investigation of Flow Phenomena and Improvement of Drain Course in Ship Ballast Tank Based on Two Phase Flow Model</title>
      <link>https://trid.trb.org/View/2329150</link>
      <description><![CDATA[The efficiency of the ballast water drainage system affects the profitability of shipping companies when loading and unloading. Moreover, the arrangement of the ballast system is closely related to the tank structure, which affects the component production and structural strength of ship. However, there is no mature design and evaluation method to balance the relationship between drainage efficiency and tank structure. This study utilizes hydraulic experiments and computational fluid dynamics (CFD) methods to verify the flow phenomenon during the drainage process in the ballast tank, so as to discuss the drainage efficiency. The model designed for the experiment data collection is a part of ballast tanks of a typical bulk carrier with the scale of 1:10. The experimental results are then validated and verified by conducting a two-phase flow model based on the volume of fluid (VOF) simulation. The research follows the order from simple to complex, starting from the single-arranged small-scale tank, and gradually expanding to the complex large-scale model. Therefore, the VOF method has been recognized in the ballast tank drainage simulation, and based on the simulation results, the drain course to improve the drainage efficiency is proposed. The results provide the reference for the design and improvement of the ballast system.]]></description>
      <pubDate>Mon, 25 Mar 2024 09:54:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2329150</guid>
    </item>
    <item>
      <title>A Study on Design Investigation Method for Drainage Plan in Ship’s Ballast Tanks by Hydraulic Model Experiment</title>
      <link>https://trid.trb.org/View/2329151</link>
      <description><![CDATA[The performance of ballast water drainage systems has a significant impact on the profitability of shipping companies. Furthermore, the arrangement of the ballast system is closely related to the tank structure, affecting the production of ship components and structural strength. However, the current state is that the design knowledge and assessment method are mainly based on the experience of the designer, and the ambiguity of design factors makes it difficult to make definite design principle.　This study uses hydraulic model experiments to analyze the complex flow phenomena in ballast tanks to provide design strategy for improving the drainage efficiency. The tank model design refers to a part of the ballast tank of a Panamax bulk carrier at a 1/10th scale, and some detailed structures are appropriately simplified. The hydraulic experiments are carried out from the small-scale ballast tank to clarify the flow phenomena between compartments, and further analysis for the impact of the drainage path on the drainage efficiency. Based on this study, a design policy for the drain course is established and verified in the hydraulic experiments based on the multi-compartment ballast tank model. The experiment results are compared with the case of the ballast tank model applying conventional design methods, and the effectiveness of the drain course is confirmed. This study provides the reference for the design and improvement of the ballast tanks design.]]></description>
      <pubDate>Mon, 11 Mar 2024 09:08:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2329151</guid>
    </item>
    <item>
      <title>Comparison of heavy metal pollution and ecological risk assessment in ballast tank sediments based on two applicable reference standards</title>
      <link>https://trid.trb.org/View/2256724</link>
      <description><![CDATA[The potential risks of ballast tank sediments have garnered global attention. This study collected sediment samples from ballast tanks of four transoceanic ships and determined 27 metal(loid) s by GB 5085.6-2007 and 9 metal(loid)s by GB 18668-2002. The pollution characteristics and ecological risk assessment of 8 typical heavy metals measured by both standards were analyzed and compared. Concentrations of Cd, Zn, and As were found to be high in the ballast tank sediments, and attention should also be directed toward Sn and Mn, which were rarely studied in ballast tank sediments. The concentration of Ni had significant differences between the two standards (P < 0.05). The results of ecological risk methods indicate that Cd, Zn, and As pose significant ecological risks. GB 5085.6-2007 demonstrated sensitivity in reflecting the ecological risks of heavy metals. Overall, this study provides valuable insights into establishing a unified standard for heavy metals for future ballast tank sediment management.]]></description>
      <pubDate>Mon, 23 Oct 2023 16:52:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2256724</guid>
    </item>
    <item>
      <title>A consistent method to design and evaluate the performance of Anti-Roll Tanks for ships</title>
      <link>https://trid.trb.org/View/2169843</link>
      <description><![CDATA[This article presents practical methods to design an Anti-Roll tank (ART) for a ship and to predict the performance of the system ship + ART in a sea state. The methods presented are extensions of existing mathematical models. The prediction of the moment exerted by the tanks has been improved and new models for the lateral force have been derived. Instead of using only the roll angle, a combination of the roll angle and the local lateral acceleration is used as excitation of the motion of the tank. The main advantage of this combined parameter is that it accounts for the distance of the tank bottom to the roll axis and the effect of sway. Experimental and CFD methods have been reviewed and results are shown. Limits of the use of the U and FS-type of ART are separately discussed and quantified. The procedure is demonstrated by a design example.]]></description>
      <pubDate>Wed, 28 Jun 2023 16:57:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2169843</guid>
    </item>
    <item>
      <title>Influence of corrosion pit geometry on stress distribution within a single artificial pit</title>
      <link>https://trid.trb.org/View/2169838</link>
      <description><![CDATA[A lower pitting severity produces a shallower corrosion pit shape on a corroded ballast tank. Pit distributions of corroded specimens have a probability model for the non-Gaussian surface. Therefore, the present work focuses on the numerical study of stress distribution within the corrosion pit area, while considering different corrosion pit geometries. Accordingly, 45 dog bone-shaped finite element models with a single corrosion pit are investigated. The geometrical parameters of the corrosion pit are analyzed with quantitative correlations at different sizes, shapes, and different levels of enlargement. Additionally, a corrosion pit alteration scenario is proposed, with a narrow deep, hemispherical, and final shallow wide form. Results show that the stress concentration factor remains relatively constant at the pit edge and increases toward the pit bottom. Furthermore, stress declines on the pit bottom and shallower corrosion pit form, which conforms to the polynomial trendline.]]></description>
      <pubDate>Wed, 28 Jun 2023 16:57:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2169838</guid>
    </item>
    <item>
      <title>Numerical analysis of the correlation between the pitting severity and surface roughness of corroded specimens</title>
      <link>https://trid.trb.org/View/2077791</link>
      <description><![CDATA[Repeated wet–dry cycle exposure to seawater during ballasting processes hastens the surface corrosion rate. Moreover, the larger volumetric changes of corroded ballast tanks generate lower pitting severity. This paper models the pitting severity of corroded ballast tanks of varying roughness and volumes. Seven rectangular finite elements models with Gaussian rough surfaces are examined. The surface roughness modelling is analyzed with correlation among corrosion-statistical parameters at various corroded specimen volume changes. Additionally, the paper elaborates the severity of pitting corrosion characteristics using the pitting factor and the relationship between the maximum and average pit depth. The pitting severity – volumetric changes scenario investigates the model’s stress distribution, showing that the greater change in volume and lower pitting severity tend to have a lower stress distribution, which is randomly concentrated on the larger area. Comparison of the theoretical results with physical test data using 3D laser scans indicates a close match.]]></description>
      <pubDate>Wed, 25 Jan 2023 09:23:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2077791</guid>
    </item>
    <item>
      <title>Optimization of operational parameters of pneumatic system for ballast tank sediment reduction with experimental and ANN applications</title>
      <link>https://trid.trb.org/View/1994364</link>
      <description><![CDATA[The studies show that ballast tank sediments pose several problems, including the continuing risk of invasive and pathogenic species transfer. Moreover, Regulation B.5 of The IMO's BWM convention states “ships should be designed and constructed with a view to minimize the uptake and undesirable entrapment of Sediments, facilitate removal of Sediments”. The purpose of the study is to investigate the effectiveness of the pneumatic system for reducing the amount of accumulated sediment under different operating conditions and determine an optimal operating condition for the pneumatic system. The experimental study has demonstrated that there are complex relationships and interactions among initial air pressure, run number, and run time in terms of reducing sediment accumulation. The overall results of this study show that sediment reduction occurs at rates ranging from ∼4% to ∼29% in sets completed under different operating conditions. Even though the total amount of the sediment was reduced in all conditions at different rates, it is figured out that the sediment amount increased in some locations within the tank. However, when operated under optimal conditions suggested by the ANN application, the sediment reduction occurred at a rate of ∼29% and there was no local increase detected throughout the tank model.]]></description>
      <pubDate>Tue, 26 Jul 2022 13:20:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/1994364</guid>
    </item>
    <item>
      <title>Investigation of heavy metals in the ballast water of ship tanks after and before the implementation of the ballast water convention: Bushehr Port, Persian Gulf</title>
      <link>https://trid.trb.org/View/1715565</link>
      <description><![CDATA[In this study, the amount of heavy metals such as Ni, Cd, Pb and Cu and some physiochemical factors including pH, temperature and total organic carbon (TOC) in the ballast water of the ships entering the Bushehr Port were measured for two years (cold and hot seasons) before and after the ballast water convention was enforced. The mean concentrations of Ni, Cd, Pb and Cu, before and after implementation of the convention were 46.55, 3.93, 5.36, 58.83 and 26.41, 2.12, 2.59, 23.54 ppb. It became clear that the concentrations of heavy metals after the implementation of the convention was lower in comparison and there was a significant difference (p < .05). It seems that continuous monitoring of the quality of the ballast water and determination of locations free of pollution and contamination in the Persian Gulf are necessary for ships that intend to exchange their ballast water in this Gulf.]]></description>
      <pubDate>Fri, 19 Nov 2021 15:27:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/1715565</guid>
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