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    <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" />
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    <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 review on flow interactions analysis using machine learning-driven CFD modelling for offshore structures and marine applications</title>
      <link>https://trid.trb.org/View/2657969</link>
      <description><![CDATA[The integration of Machine Learning (ML) and Computational Fluid Dynamics (CFD) could become a paradigm shift in marine engineering applications. This review deals with the current state-of-the-art on the recent progress in the implementation of ML methods on marine-related CFD problems. This paper presents the use of CFD in the marine application world, such as the flow analysis over rectangular cylinders, wind turbine foundations and submerged structures under wave action. However, the supervised, unsupervised and semi-supervised methods are also discussed critically. The paper also discusses the use of ML in the prediction of vessel shaft power, fuel consumption, propeller analysis, structural damage inspection and possibly autonomous hull maintenance. The present overview is also focused on the CFD-based ML models to simulate the turbulent flows, predict fluid field and pressure drops, analyse turbine wake and blade loads, generate pump performance maps, and assess offshore structure response, namely vortex-induced vibrations.]]></description>
      <pubDate>Wed, 24 Jun 2026 11:31:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2657969</guid>
    </item>
    <item>
      <title>Seismic centrifuge modelling of repowered offshore wind turbine considering monopile foundation strengthening and superstructure replacement</title>
      <link>https://trid.trb.org/View/2660595</link>
      <description><![CDATA[Numerous offshore wind turbines (OWTs) are now approaching end-of-life (EoL). As an economical and sustainable strategy, repowering is commonly used for EoL scenarios. However, there is limited research on the service performance of repowered OWTs during their extended life, particularly concerning the seismic performance. In this study, a series of centrifuge shaking table tests was conducted to investigate the dynamic characteristics and seismic responses of the repowered monopile-supported OWT. Specifically, the original 2 MW turbine superstructure was upgraded with corresponding 3 MW components while retaining the serviceable foundation. Before repowering, solidified soil remediation was employed to enhance foundation performance in response to scour, a common phenomenon around marine foundations caused by currents. The results show that replacing the superstructure (upgraded to 3 MW turbine) reduces the natural frequencies of the OWT. Additionally, structural accelerations and displacements are changed under different earthquakes, while peak rotation and bending moments of the foundation at the mudline are amplified. These findings indicate potential risks of structural resonance and excessive deformation in repowered wind turbines. It is necessary to reassess modal characteristics and seismic performance during their extended service life to ensure the reliability of upgrade and maximize the long-term benefits of OWTs.]]></description>
      <pubDate>Wed, 29 Apr 2026 09:10:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2660595</guid>
    </item>
    <item>
      <title>Optimization method for jacket platforms using random forest surrogate model</title>
      <link>https://trid.trb.org/View/2638272</link>
      <description><![CDATA[The optimization of jacket platforms typically relies on computationally intensive finite element analysis (FEA), which is relatively time-consuming. Surrogate models are widely used in multi-domain optimization problems, while machine learning algorithms are employed to construct surrogate models, demonstrating promising applications. In this study, an optimization method that integrates machine learning surrogate models with an improved genetic algorithm (GA) is employed to enhance structural optimization efficiency. Then, the proposed method is applied to a typical jacket platform in the Bohai Sea using a seven-dimensional optimization space designed to minimize the total structural weight. A surrogate model is derived through a random forest algorithm to replace FEA. The surrogate model is combined with a real-coded GA featuring adaptive crossover and mutation for iterative optimization. Moreover, surrogate models are developed using Decision Tree and KNN methods. Evaluation results show that the random forest algorithm outperforms Decision Tree and KNN methods. The random forest surrogate model can save significant computation time while maintaining high accuracy, providing an efficient and effective alternative to the FEA optimization method.]]></description>
      <pubDate>Mon, 27 Apr 2026 15:01:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/2638272</guid>
    </item>
    <item>
      <title>Contribution of the wheel action to the horizontal anti-vibration ability of the coupled monopile-wheel composite foundation</title>
      <link>https://trid.trb.org/View/2660825</link>
      <description><![CDATA[In this paper, a mechanical model is presented to investigate the horizontal vibration of the pile-wheel composite foundation with coupled arrangement. Firstly, based on Timoshenko beam theory, a series of differential equations of the pipe pile in composite foundation are derived to obtain deﬂections and rotation angles along the pile shaft, where the soil behavior under the action of vibrating pile and wheel is idealized by Winkler's foundation expressions. The input parameters of the dynamic Winkler model, i.e. the springs and dashpots, are determined by the Novak's thin-layer method and the Biot's three-dimensional wave equation. Subsequently, the transfer matrix method is applied to consider the force contact and displacement continuity conditions at different pile segments with the foundation dynamic characteristics in the frequency domain obtained as well. After verifying the correctness and reasonableness of the analytical framework via the comparison with available theoretical solutions and finite element simulations, further parametric analysises are carried out to discuss the contribution of the wheel action to the horizontal anti-vibration ability of this innovative offshore foundation. The numerical study indicates that the horizontal resistance applied on the wheel side is more effective than others actions provided by the wheel.]]></description>
      <pubDate>Thu, 23 Apr 2026 09:12:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2660825</guid>
    </item>
    <item>
      <title>Reducing local scour around monopiles using arc-shaped sacrificial piles under unidirectional flow</title>
      <link>https://trid.trb.org/View/2660633</link>
      <description><![CDATA[Traditional cylindrical sacrificial pile groups may exacerbate local scour around monopile foundations due to complex vortex interactions. To provide a more efficient active flow-diversion countermeasure, this study proposes a novel arc-shaped sacrificial pile. Clear-water scour experiments are conducted to quantify the effects of flow intensity (FI), clearance between sacrificial pile and monopile (L1), pile height (H1), inflow attack angle (ω), number (n1) and spacing (W1) of sacrificial piles, and the arc orientation (convex-vs. concave-upstream) on scour evolution and equilibrium bed morphology. Owing to its streamlined geometry, the arc-shaped pile diverts the flow laterally, thereby reducing both approach velocity and bed shear stress upstream of the monopile. Under the optimal conditions (ω of 0° and L1/D of 0.5, where D is the monopile diameter), the maximum scour depth around the monopile is reduced by 60 % relative to the unprotected case. Three protection mechanisms are identified as L1/D varies: (i) intimate shielding (L1/D = 0.5), where the pile pair behaves as a compound body; (ii) weakened flow-field coupling (L1/D = 1.0–1.5); and (iii) remote sediment backfilling (L1/D = 2.0), where sediment eroded around the sacrificial pile partially refills the monopile scour pit. Side-by-side layouts may generate a high-velocity gap jet that markedly diminishes protection, and the convex-upstream orientation consistently outperforms the concave-upstream orientation in flow diversion and stabilization.]]></description>
      <pubDate>Wed, 22 Apr 2026 16:13:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/2660633</guid>
    </item>
    <item>
      <title>Experimental investigation on lateral response and failure mechanisms of distributed post-grouted drilled shafts in sandy soils</title>
      <link>https://trid.trb.org/View/2660616</link>
      <description><![CDATA[This study systematically investigates the lateral response of drilled shaft foundations in sandy soils, with a specific focus on the innovative distributed post-grouting technique, which is highly relevant for offshore foundations subjected to significant lateral loads. Comparative model tests were conducted on ungrouted, conventional post-grouted, and distributed post-grouted drilled shafts. The results demonstrate that distributed post-grouting markedly enhances lateral capacity, showing improvements of 98.0 % and 28.4 % over the ungrouted and conventional post-grouted shafts, respectively. It also optimizes the bending moment distribution and increases lateral soil resistance. A three-dimensional finite element model, validated against experimental excavation data, was developed and reveals that the distributed post-grouted shafts undergo primarily flexible deformation, with a distinct, uniformly deformed wedge-shaped failure zone extending to a depth of 0.4 m in the soil behind the shaft. Furthermore, analysis using the strain wedge theory elucidates that the grouting volume enhances lateral bearing performance by optimizing the stress distribution in the surrounding soil. This enhancement, however, is particularly significant within a specific grouting volume range. The findings provide critical insights for optimizing grouting strategies to improve the performance of drilled shaft foundations in demanding offshore applications.]]></description>
      <pubDate>Tue, 21 Apr 2026 14:30:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2660616</guid>
    </item>
    <item>
      <title>Numerical limit evaluations of the pullout capability of vertical strip plate anchor in anisotropic soil</title>
      <link>https://trid.trb.org/View/2649731</link>
      <description><![CDATA[The effectiveness of plate anchors in anisotropic soil conditions are essential for the design of both offshore and onshore foundation systems. This study presents a thorough numerical limit analysis to assess the pullout capacity of vertical strip plate anchors embedded in anisotropic soil. Using lower and upper bound limit analysis methods through finite element modeling, how strength anisotropy, embedment depth, and soil layering affect anchor performance is rigorously examined. The results show a clear sensitivity of the pullout capacity to the degree and orientation of anisotropy. This highlights the limitations of isotropic assumptions in some geotechnical design cases. Parametric studies further explain the relationship between anisotropic strength parameters and anchor resistance. These insights can improve stability and safety margins. These findings deepen the understanding of anchor–soil interaction under complex conditions and aid in crafting more accurate and efficient design methods for geotechnical engineers.]]></description>
      <pubDate>Fri, 03 Apr 2026 12:12:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2649731</guid>
    </item>
    <item>
      <title>Dynamic response analysis of integrated jacket offshore wind turbine foundation and aquaculture cage structure under regular waves</title>
      <link>https://trid.trb.org/View/2647541</link>
      <description><![CDATA[Wind-fishery integration, a novel development model combining offshore wind power and marine aquaculture, effectively addresses marine resource conflicts. This study presents an innovative marine integrated structure (JOWT+AC), combining jacket-foundation offshore wind turbines (JOWT) with aquaculture cages (AC). The numerical simulation method was first validated using data from physical model experiments, and then used to analyze the dynamic response of the structure. Results indicate that pile loads, leg stresses, and displacements are most affected by wave period, along with wave height and incidence angle. Bottom rope tensions in AC are significantly higher than top ones, with JOWT+AC-M2 (with a total of 12 mooring points) and M3 (with a total of 20 mooring points) showing about 32 % of M1’s (with a total of 8 mooring points) bottom rope tension, while top tensions remain similar. A middle rope section aids in load redistribution, while different mooring configurations influence load paths and structural stiffness. The AC’s damping effect reduces the JOWT+AC dynamic response compared to standalone JOWT. This study offers theoretical guidance for sustainable JOWT+AC design through combined physical and numerical modelling.]]></description>
      <pubDate>Fri, 27 Mar 2026 10:14:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/2647541</guid>
    </item>
    <item>
      <title>Dynamic behavior and stiffness degradation of fine-grained gassy soils under cyclic loading</title>
      <link>https://trid.trb.org/View/2642095</link>
      <description><![CDATA[The dynamic behavior of fine-grained gassy soils under cyclic loading remains unclear, particularly regarding small-strain properties and stiffness degradation. This study investigates the effects of gas content, cyclic stress ratio (CSR), and frequency on these responses using triaxial tests and bender element measurements. Results show gas content significantly influences strain accumulation: higher gas levels exacerbate permanent axial strain and pore pressure buildup under increased CSR, with stiffness degradation accelerating as stress amplitude rises. Both dynamic elastic modulus and small-strain shear modulus (Gₘₐₓ) decrease with CSR, though Gₘₐₓ degrades less prominently, highlighting distinct deformation mechanisms across strain scales. Gas presence amplifies modulus reduction, especially at low frequencies, due to restricted bubble mobility. This work underscores gas content as a critical factor in modulating cyclic response, revealing that even moderate gas inclusion alters soil stiffness and strain behavior. Findings advance understanding of gassy soil dynamics, informing offshore foundation design in gas-rich environments.]]></description>
      <pubDate>Fri, 20 Mar 2026 14:47:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2642095</guid>
    </item>
    <item>
      <title>Lateral bearing characteristics of an innovative tetrapod bucket foundation for offshore wind turbines</title>
      <link>https://trid.trb.org/View/2641325</link>
      <description><![CDATA[The increasing water depth of offshore wind farms and the development of large-capacity units place higher demands on the bearing characteristics of wind turbine foundations. The multi-bucket jacket foundation has the advantages of high rigidity and good bearing capacity, and has been widely used in recent years. This paper investigates the lateral ultimate bearing characteristics of an innovative tetrapod bucket foundation with a connection structure through model tests, focusing on comparing and analyzing the influence of loading mode, drainage conditions, aspect ratio, and connection structure on the lateral ultimate bearing capacity of the foundation. The results reveal that the inclusion of the connection structure improves the lateral bearing capacity of the tetrapod bucket foundation, which can be increased by more than 10 % under undrained conditions. The loading direction, undrained conditions and aspect ratio have significant effects on the bearing capacity of the tetrapod bucket foundation. Additionally, a superimposed amplification effect on the bearing capacity of the tetrapod bucket foundation is observed in comparison with the monopod bucket foundation.]]></description>
      <pubDate>Fri, 20 Mar 2026 14:47:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2641325</guid>
    </item>
    <item>
      <title>Shape and stress sensing of wind turbine jackets using the static condensation inverse finite element method</title>
      <link>https://trid.trb.org/View/2644008</link>
      <description><![CDATA[To mitigate the dense sensor requirement of conventional inverse finite element methods (iFEM) in structural health monitoring of offshore wind-jacket foundations, an improved formulation (iFEM-S) is developed by integrating static condensation theory. The jacket is hierarchically decomposed into (i) a primary-leg master structure that accommodates strain gauges and (ii) X-brace substructures whose degrees of freedom are statically condensed. Only discrete strain data from the primary legs are acquired. Remarkably, full-field displacement and stress fields are accurately reconstructed using only discrete strain data from the primary legs—requiring just 64 sensors (4.9 % of total elements). Numerical validation demonstrates that the proposed iFEM-S markedly outperforms the traditional iFEM. At the instant of peak structural response, the displacement reconstruction accuracy, quantified by the coefficient of determination R², improves by 122.7 %, axial strain accuracy by 30.6 %, and bending strain accuracy by 1 %. Moreover, the feasibility of replacing the physical stiffness matrix with an equivalent stiffness matrix is further investigated. Although this substitution reduces bending-strain accuracy by 5.6 %, it eliminates the need for material parameters, rendering the approach attractive for scenarios involving material degradation. By substantially lowering the monitoring cost, iFEM-S provides a novel pathway for health monitoring and the digital twin implementation of deep-water wind-jacket foundations.]]></description>
      <pubDate>Fri, 20 Mar 2026 14:47:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/2644008</guid>
    </item>
    <item>
      <title>Experimental study of fiber-reinforced cemented soil: material characteristics and scour repair performance for monopile foundations</title>
      <link>https://trid.trb.org/View/2644092</link>
      <description><![CDATA[Local scour at monopile foundations presents a critical risk to the stability of offshore structures. This study introduces a novel fiber-reinforced cemented soil (FRCS) for scour repair. Laboratory experiments were conducted to investigate the effects of fiber types and content on the characteristics of cemented soil (CS), as well as the effect of curing time(T) on critical starting velocity. Additionally, the performance of scour repair and the dynamic response of the monopile were examined. Results indicated that the addition of fibers improved the underwater anti-washout property and the unconfined compressive strength (UCS) of CS, but decreased its flowability. Fibers with higher elastic modulus significantly enhanced scour resistance of CS. The addition of fibers can improve the scour repair performance of the CS, with Polyvinyl alcohol fiber and basalt fiber-reinforced CS exhibiting the best performance. Extended curing time improved repair performance. The scour loss rate of PVAF-reinforced CS decreased significantly from 23.6 % at T = 1h to 4.5 % at T = 2h under high-velocity flow conditions. Furthermore, the application of FRCS suppressed the vibration response at the pile head, indicating an improvement in lateral stiffness. This study can provide a reference for the application of FRCS in monopile foundations scour repair engineering.]]></description>
      <pubDate>Tue, 17 Mar 2026 09:48:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2644092</guid>
    </item>
    <item>
      <title>Upper bound solution of the moment capacity of the pile-bucket composite foundation</title>
      <link>https://trid.trb.org/View/2641284</link>
      <description><![CDATA[The pile-bucket composite foundation has attracted considerable attention as an innovative offshore foundation system, and accurately assessing its ultimate moment capacity is critical to ensuring engineering security. In this study, the moment capacity characteristic and associated failure mechanisms of composite foundations were explored through model tests and FEM simulations. The results revealed that the composite foundation approximately exhibits two distinct patterns of symmetric circular rotational failure under moment loading. When the ratio of H/D ≤ 1/2, both the moment capacity coefficient and the rotation center position remain nearly constant as H/D increases. For 1/2 <H/D ≤ 1, the failure zone retains an overall coherent shape, while the rotation center shifts downward and the moment capacity coefficient increases with H/D. Two kinematically admissible velocity fields with distinct boundary conditions were established, and the ultimate moment capacity with varying H/D ratios was derived using the upper-bound theorem. The theoretical solutions showed good agreement with the model test and numerical results, with maximum and minimum errors of 6.896 % and 0.398 %, respectively. This validated method presents a theoretical framework for evaluating the ultimate moment capacity of composite foundations and offering valuable insights for the design and optimization of offshore wind turbine substructures.]]></description>
      <pubDate>Wed, 11 Mar 2026 14:41:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/2641284</guid>
    </item>
    <item>
      <title>Dynamic response of suction bucket jacket foundation for a wind turbine under storm environments</title>
      <link>https://trid.trb.org/View/2637920</link>
      <description><![CDATA[To investigate the dynamic response of the SBJ-supported OWTs located in sandy soil under storm environments, a series of model tests and numerical analyses were carried out where three loading levels and three loading modes were considered. The model test results indicate that the maximum horizontal displacement of OWTs increases significantly with structure height and typhoon intensity. The wind load caused the main displacement and vibration of the structure, and wave loads exert a rather complex effect on the wind-induced vibration under the coupled loads. For the foundation, the vertical displacements and soil pressures of the front bucket are always larger than those of the rear buckets, the former is mainly excited by wind loads, while the later is mainly induced by wave loads. The numerical simulation showed that the plastic soil strain range near the front bucket bottom is greater than the rear bucket under the wind load, and it is similar under the wave load. The resistance of SBJ foundation is mainly provided by the soil around the front bucket. The vertical positions of the rotation center gradually upward with the increase of typhoon intensity, and the horizontal position is nearly unchanged.]]></description>
      <pubDate>Tue, 10 Mar 2026 09:55:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2637920</guid>
    </item>
    <item>
      <title>Envelope of bearing capacity for gravity anchors in strain-softening soils under VHM loading: A Cosserat continuum FEM study</title>
      <link>https://trid.trb.org/View/2612148</link>
      <description><![CDATA[In offshore foundation bearing capacity analysis, the failure envelope method is widely used because it clearly separates load components. However, previous studies on the bearing capacity of gravity anchors under combined loads have not effectively accounted for soil strain-softening behavior. To address this limitation, a Mohr-Coulomb-matched Drucker-Prager model is adopted within the Cosserat continuum framework (MC-matched DP model). Numerical simulations were conducted using Abaqus’s user-defined element (UEL) functionality. Validation against existing literature confirms the accuracy and applicability of the Cosserat continuum model for analyzing the bearing capacity of gravity anchors under VHM combined loading conditions. This approach successfully resolves numerical convergence difficulties and pathological mesh dependency issues commonly observed in finite element analyses of strain-softening soils. The model was then applied to conduct a comprehensive analysis of the bearing capacity envelopes of gravity anchors. Through parametric studies, the influences of anchor embedment depth, vertical load magnitude, and strain-softening degree on the bearing capacity envelope were systematically investigated. Normalized bearing capacity envelope formulas were derived for various scenarios, providing a robust framework for evaluating the performance of gravity anchors under different conditions.]]></description>
      <pubDate>Mon, 02 Mar 2026 08:55:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2612148</guid>
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