<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>Investigation of powder mixing methods on the energy absorption performance of graphene-reinforced cylindrical composite tubes</title>
      <link>https://trid.trb.org/View/2709451</link>
      <description><![CDATA[In this study two methods were chosen for the production of composites: vacuum infusion and hand lay-up. The effect of varying the graphene addition method on the mechanical properties of the composite material was investigated. The first method involved adding graphene to the epoxy resin and infusing it into the fibre. The second method involved adding graphene dissolved in an acetone to the fibre. Quasi-static compression tests were applied to the samples, and the resulting energy absorption values (EA), specific energy absorption values (SEA), and peak forces (PF) were compared. The greatest EA was obtained with 200.42 joules with graphene-free epoxy resin matrix glass fibre produced by vacuum-infusion. The lowest EA was obtained with 132.32 joules with the sample produced by hand lay-up. In terms of PF values, the highest result was observed with 6.45 kN in the sample which graphene added in acetone solution.]]></description>
      <pubDate>Mon, 29 Jun 2026 09:11:40 GMT</pubDate>
      <guid>https://trid.trb.org/View/2709451</guid>
    </item>
    <item>
      <title>Performance of Glass-Based Geosynthetic Reinforced RAP Bases for Unpaved Road Applications</title>
      <link>https://trid.trb.org/View/2678556</link>
      <description><![CDATA[The United States classifies over 1.3 million miles of its roadway network as unpaved and low-volume roads, which constitutes nearly 35% of the transportation infrastructure of the country. A significant portion of it consists of local and rural roads, which play a crucial role in connecting remote communities. Construction of these low-volume roads (LVRs) with Reclaimed Asphalt Pavement (RAP) base could potentially be a sustainable and cost-effective alternative to virgin aggregate base. However, the usage of RAP in pavement layers comes with several challenges such as reduced strength and stiffness, moisture susceptibility, and variable material properties. These drawbacks directly affect the pavement performance under repeated traffic loading, resulting in higher settlement and long-term deformations. In order to overcome the shortcomings and improve the performance of the pavements, the use of geosynthetics is a promising solution. The performance of conventional geosynthetics, such as geogrids and geotextiles is well-studied and proven to show significant improvement as reinforcing material. However, non-traditional geosynthetics, such as glass-based geosynthetics for base layer reinforcement, have been investigated minimally. Hence, this study explores using two different glass-based geosynthetics, GlasPave (GP) and GlasGrid (GG), as base layer reinforcement for RAP to improve the pavement performance. An experimental study was performed on unreinforced and reinforced sections with a 100% RAP base using large-scale cyclic plate load tests. From the test results, it was observed that the unreinforced section exhibited low stiffness and failed with a surface deformation of over 3 in. under 3,000 load cycles. Whereas the reinforced sections that were constructed with GP and GG installed at the mid-depth of RAP base layer showed significantly high stiffness and resulted in 50% to 75% less surface deformation when compared to the unreinforced RAP base section.]]></description>
      <pubDate>Fri, 12 Jun 2026 15:59:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/2678556</guid>
    </item>
    <item>
      <title>Evaluating the impact of sandwich composite integrated superstructures on the longitudinal bending strength of ships</title>
      <link>https://trid.trb.org/View/2632850</link>
      <description><![CDATA[The research object is a scaled ship model based on the actual size of the naval ship. Firstly, numerical calculations and four-point bending tests are used to obtain the stresses and deformations at the measured points of the model under the hogging and sagging cases, and then to analyse the load-bearing moment of each longitudinal structure on a typical cross-section. Afterwards, combined with the static test of the scaled-down model, the effectiveness of sandwich composite integrated superstructure participating in the total longitudinal bending of the hull is calculated, and then the mechanism of its participation in the total longitudinal bending is analysed. Finally, the paper explores the influence of the dimensions of the main longitudinal structures in the integrated superstructure, the structural materials of the superstructure, and its structural form, on the mechanism of the integrated superstructure's participation in the total longitudinal bending of the hull.]]></description>
      <pubDate>Mon, 27 Apr 2026 14:59:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2632850</guid>
    </item>
    <item>
      <title>A novel solidified soil material for protecting offshore wind turbine foundations against wave-induced scour: Experimental study and mechanism analysis</title>
      <link>https://trid.trb.org/View/2653062</link>
      <description><![CDATA[Scour around monopile foundations induced by combined wave action is a critical threat to the stability of offshore wind turbines. To address this challenge, a novel glass fiber-reinforced cement-based composite solidified soil was developed for seabed foundation protection. This study comprehensively evaluated the performance of this material through an integrated experimental program designed to decouple the key scour mechanisms: cyclic triaxial tests were conducted to simulate the soil's response to wave-induced cyclic loading, while flume tests assessed its resistance to extreme current-induced scour. The results demonstrate that under long-term high-strength cyclic loading, the solidified soil exhibits superior performance, including significantly lower cumulative strain, higher dynamic elastic modulus, and increased damping ratio, indicating enhanced resistance to cyclic deformation. Flume tests further confirmed its exceptional anti-scouring capacity, with a dramatically lower mass loss rate compared to undisturbed soil under extreme flow velocities. Microstructural analysis revealed that the synergy of chemical bonding and physical reinforcement by glass fibers creates a more integral and compact soil fabric, which is the fundamental mechanism for the improved macro-scale performance. The findings confirm that the proposed solidified soil offers an effective solution for scour protection, providing both practical and theoretical support for safeguarding offshore wind turbine foundations.]]></description>
      <pubDate>Wed, 08 Apr 2026 13:57:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/2653062</guid>
    </item>
    <item>
      <title>Marine Coolant Fluids’ Effect on the Mechanical Properties of Glass Fiber-Reinforced Composites</title>
      <link>https://trid.trb.org/View/2676070</link>
      <description><![CDATA[This study examines the effect of coolant and antifreeze solutions such as distilled water, ethylene glycol-based antifreeze with organic acid technology (OAT), and ethylene glycol-based antifreeze with inorganic inhibitors and glycerol (iat/hoat) on the tensile strength of glass fiber-reinforced polyester (GFRP-P) and vinyl ester (GFRP-VE) composites. Standardized specimens were produced and immersed in these solutions for three months at room temperature. Following exposure, tensile tests were conducted using the universal testing machine, supported by microscopic analysis to evaluate surface damage and internal structural changes such as composite layer delamination. The tensile test results show the highest decrease in tensile strength for GFRP-P specimens immersed in HOAT antifreeze (16.3%), whereas GFRP-VE specimens exhibit only a minimal reduction (3.4%). This difference is attributed to the higher chemical aggressiveness and alkalinity of the HOAT antifreeze. Furthermore, the decrease in the tensile strength of GFR-P exposed to OAT antifreeze is 6.1%, whereas GfrP-Ve demonstrates a significantly smaller reduction of 1%, which can be attributed to the less aggressive chemical composition of the OAT formulation compared to HOAT. In contrast, the influence of distilled water on GfrP-P specimens is manifested as a tensile strength decrease of 12.7%, whereas GfrP-Ve specimens show a reduction of 11%, attributed to the fluid’s density and the rate of hydrolytic degradation. These results contribute to a deeper understanding of the effects of various coolant media on the performance of GFRP in marine cooling systems, highlighting GFRP-VE as a more suitable matrix for prolonged exposure to coolant environments.]]></description>
      <pubDate>Wed, 25 Mar 2026 11:44:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2676070</guid>
    </item>
    <item>
      <title>Influence of the PTFE on the Tribological and Mechanical Properties
          of a Fiber-Reinforced Polyphthalamide</title>
      <link>https://trid.trb.org/View/2669830</link>
      <description><![CDATA[Materials science and engineering are essential for advancing energy-efficient                     mechanical systems through lightweight structures and friction reduction. Among                     engineering polymers, polyphthalamides (PPA) are widely used for their superior                     thermochemical and mechanical properties. This study investigates the influence                     of polytetrafluoroethylene (PTFE) on the mechanical and tribological performance                     of a commercial polymer matrix composite (PMC) reinforced with 30wt% glass                     fiber. Self-lubricating composites were manufactured by injection molding with                     PTFE contents ranging from 0-15 wt%. Density was measured using Archimedes’                     method. Mechanical properties were measured through ISO 527 tensile testing,                     while tribological behavior was evaluated using ball-on-flat reciprocating tests                     under 189N (630 MPa), 2 H frequency, and 10 mm strokes for 60 minutes, employing                     a 10 mm diameter AISI 52100 steel sphere as counter-body. Friction coefficient                     (COF) was monitored throughout testing, and wear mechanisms were investigated                     using white-light interferometry (WLI), scanning electron microscopy (SEM), and                     energy-dispersive X-ray spectroscopy (EDS). Wear volumes were obtained from                     contact profilometry. Results show that PTFE addition reduced mechanical                     strength decreasing by 7.9%, 8.5% and 14.8% for 2%, 5% and 15% PTFE,                     respectively. In contrast, tribological performance improved, with COF                     stabilizing between 0.03-0.08 and wear rate decreasing from 5.6 ×                     10-4 mm3/N.m (no lubricant) to 1.0 × 10-4                     mm3/N.m for 2 and 5% PTFE. At 15% PTFE, wear rate and COP                     increased to 2.3 × 10-4 mm3/N.m and 0.08, respectively.                     EDS analysis detected fluorine on the wear surfaces, confirming the formation of                     PTFE-rich tribolayers. However, excessive PTFE compromises mechanical integrity                     due to the formation of large reservoirs, leading to increased deformation and                     wear under high pressure. Thus, optimal performance results from balancing PTFE                     content and mechanical in robustness.]]></description>
      <pubDate>Tue, 17 Feb 2026 10:32:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2669830</guid>
    </item>
    <item>
      <title>Investigation of Particulate Matter Emissions from Brake Pads of
          Light-Duty Vehicles: A Comparative Analysis of Friction Material
          Compositions</title>
      <link>https://trid.trb.org/View/2669828</link>
      <description><![CDATA[Studies correlate air pollution with an increase in the incidence of respiratory                     diseases, affecting lung function and raising hospitalization rates. Among the                     pollutants associated with these diseases, inhalable coarse particulate matter                     (PM10) and fine particulate matter (PM2.5) stand out.                     The emission of particulate matter resulting from the wear of brake pads in                     light vehicles is the second largest source, accounting for approximately 33% of                     a vehicle’s total emissions. The particulate matter generated during the braking                     process can be analyzed through its collection in tests conducted on                     dynamometers, using enclosure and sampling systems. The development of the                     dynamometer used was based on the braking cycles described in the SAE J2522:2003                     standard, whose main objective is to provide comparative data on different                     friction materials. Given the variations in particulate matter emissions                     depending on the composition of the brake pads, as reported in the literature,                     this study presents an analysis of the emissions from two distinct formulations,                     as well as a comparison of wear parameters and the surface roughness of the                     pads. The characterization of the particulate matter was carried out using a                     sampling system in accordance with ISO 9096:2017, with a sampling duct aligned                     with the flow duct downstream of the enclosure chamber, and particle retention                     achieved through fiberglass filters. The airflow velocity was controlled to                     ensure isokinetic transport conditions in the sampling system, adjusting the                     connected pump to match the probe velocity. The results show that wear was not                     uniform between the pairs of brake pads, also revealing differences in the                     chemical composition of the particulate matter according to the different                     formulations, consistent with what is reported in the literature, but with                     similar particle concentrations by size.]]></description>
      <pubDate>Tue, 17 Feb 2026 10:32:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2669828</guid>
    </item>
    <item>
      <title>Injection Molding Parameters Optimization to Enhance Mechanical
          Properties of Glass-Fiber Reinforced PA9T Polymer</title>
      <link>https://trid.trb.org/View/2669813</link>
      <description><![CDATA[The use of polymeric materials and polymer -based composites as alternatives to                     metals in conventional applications is a widely adopted strategy. These                     materials provide advantages in terms of processability, cost-effectiveness,                     and, most notably, weight reduction. This study aimed to develop and optimize                     the injection molding process for producing PA9T (Polyphthalamide 9T) components                     reinforced with varying amounts of glass fiber to achieve optimal mechanical and                     physical properties. To enhance mechanical performance, different glass fiber                     loadings were investigated. The study employed the Taguchi method with an L9                     orthogonal array design. The selected variable parameters were material                     composition (PA9T reinforced with 30, 35, and 50 wt% glass fiber), injection                     pressure (1000, 1500, and 2000 bar), injection temperature (320, 330, and 340                     °C), and injection speed (100, 125, and 150 mm/s). The Taguchi method was chosen                     because it allows for the identification of optimal process parameters and the                     evaluation of their influence on material properties while requiring                     significantly fewer experimental runs compared to a full-factorial 34                     design. The materials were evaluated based on mechanical properties through                     tensile and flexural tests using a Universal Testing Machine. The density of the                     injected specimens was measured using the Archimedes principle, while                     fiber-matrix adhesion, porosity morphology, and fracture behavior were analyzed                     via scanning electron microscopy (SEM). Results indicated that the glass fiber                     content had the most significant influence on material strength, followed by                     injection pressure, temperature, and speed, in that order. The study identified                     1000 bar, 320 °C, and 100 mm/s and 50 wt% glass fiber as the optimal processing                     parameters, ensuring that specimens produced under these conditions achieved                     mechanical properties such as 230 MPa stress at break and elastic modulus of                     19,3 GPa.]]></description>
      <pubDate>Tue, 17 Feb 2026 10:32:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2669813</guid>
    </item>
    <item>
      <title>Genetic Algorithm Based Optimization of Chaboche Kinematic Hardening Parameters along with the Validation of FE Model through Characterized Crack Initiation</title>
      <link>https://trid.trb.org/View/2669792</link>
      <description><![CDATA[In the context of electro-mobility for commercial vehicles, the failure analysis of a connector panel in a DCDC converter is crucial, particularly regarding crack initiation at the interface of busbar and plastic component. This analysis requires a thorough understanding of thermo-mechanical behavior under thermal cyclic loads, necessitating kinematic hardening material modeling to account for the Bauschinger effect. As low cycle fatigue (LCF) test data is not available for glass fiber reinforced polyamide based thermoplastic composite (PA66GF), we have adopted a novel approach of determining non-linear Chaboche Non-Linear Kinematic Hardening (NLK) model parameters from monotonic uniaxial temperature dependent tensile test data of PA66GF. In this proposed work a detailed discussion has been presented on manual calibration and Genetic Algorithm (GA) based optimization of Chaboche parameters. Due to lack of fiber orientation dependent test data for PA66GF, here von Mises yield criteria based Chaboche NLK model is implemented as a macro-mechanical phenomenological model based on test data with random fiber orientation. After material modelling as described above the thermo-mechanical finite element (FE) simulation has been conducted on Connector panel assembly with temperature cycling from -40°C to 80°C. The assembly under consideration is composed of busbars, insert mold and outer connector body of plastic PA66GF. It is observed from the simulation result that though the equivalent plastic strain is much higher at 80°C in comparison to the same at -40°C, the equivalent von Mises stress is comparatively lower at 80°C than at -40°C because of Bauschinger effect while reversing load, which in turn validates the implementation of proper kinematic hardening material model to address the physical phenomenon. Finally, the FE model is validated through characterized crack initiation site in the plastic component comparing with equivalent plastic strain, von Mises stress and stress triaxiality evaluated from simulated result.]]></description>
      <pubDate>Tue, 17 Feb 2026 10:28:09 GMT</pubDate>
      <guid>https://trid.trb.org/View/2669792</guid>
    </item>
    <item>
      <title>The catastrophic failure of thick composite cylindrical pressure hulls: Analytical, numerical and experimental investigations</title>
      <link>https://trid.trb.org/View/2640985</link>
      <description><![CDATA[The catastrophic failure of thick composite cylindrical pressure hulls under high external hydrostatic pressure was investigated by analytical, numerical and experimental methods. Buckling failure and material failure were both considered to identify which failure mode of such thick hulls initiates first. An elastic buckling analytical model for thick composite cylinders based on Sander theory principles was applied to derive the critical buckling load. Meanwhile, a progressive damage model (PDM) was developed to simulate the material behavior in the region between the first-ply failure and ultimate failure, and the effects of failure criteria and geometrical defects on the implosion load of the test model were investigated. Then ultimate strength were obtained by comprehensive analysis of buckling failure and material failure via analytical and numerical methods. A group of two thick T700 carbon fiber/epoxy composite cylindrical pressure hulls were designed and manufactured, hydrostatic pressure tests were conducted to derive the catastrophic failure characteristics of thick composite pressure hulls and to validate the analytical and numerical results and methodology for the failure analysis of thick composite cylindrical pressure hulls.]]></description>
      <pubDate>Fri, 09 Jan 2026 16:59:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2640985</guid>
    </item>
    <item>
      <title>Interfacial Shear Transfer for Concrete Elements with Non-Corrosive Composite Reinforcement </title>
      <link>https://trid.trb.org/View/2646936</link>
      <description><![CDATA[This project will investigate a novel approach to enhance the dowel resistance of Glass Fiber Reinforced Polymer (GFRP) bars when used as shear reinforcement construction of concrete bridges. Fiber reinforced polymer is known to be resistant to corrosion with potential benefits in bridge construction. However, it has low dowel action resistance, which can jeopardize the integrity of the composite action between precast/prestressed concrete and cast-in-place bridge deck slabs, which can lead to failure of the bridge girder system. Improving the dowel action resistance of GFRP stirrups will eliminate a barrier to wider adoption of non-corrosive GFRP bars in bridge construction. The objective of this project is to explore a novel approach whereby GFRP dowels will be placed at an angle to the shear interface between the precast beam and the cast-in-place deck for enhancing the horizontal shear resistance of fiber reinforced polymer dowels for the purpose of ensuring composite action in bridges built with non-corrosive reinforcement.  

The scope of the project is limited to GFRP bars, which is the most widely used rebar alternative due to its lower cost and acceptable properties compared to other types of fiber reinforced polymer bars. The contribution of the GFRP bars to the mechanism of shear transfer will be evaluated by using push-off specimens that have been successfully used for studying dowel action of steel bars. Push-off specimens with non-orthogonal GFRP dowels at two angles and two spacings are proposed to be tested experimentally along with a control specimen. The proposed specimens will explore the effect of different angles and dowel spacing on the interfacial shear resistance between concrete elements with GFRP dowls. ]]></description>
      <pubDate>Mon, 05 Jan 2026 22:26:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2646936</guid>
    </item>
    <item>
      <title>Optimization and field evaluation of a detachable thermal insulation fabric for rail temperature mitigation</title>
      <link>https://trid.trb.org/View/2616650</link>
      <description><![CDATA[Rail temperature control is a critical factor in ensuring the safety and reliability of railway systems, especially under extreme summer heat conditions. Conventional countermeasures such as water spraying systems and solar-reflective coatings have demonstrated limited applicability due to high installation and maintenance costs, short duration of cooling effects, and practical constraints in field deployment. As a novel solution, this study introduces and validates a detachable thermal insulation fabric designed for steel rails, consisting of a heat-reflective fluoropolymer-coated glass fiber fabric and embedded magnets for easy installation and reuse. Through controlled laboratory tests, the optimal coating thickness (100 μm) and effective application area (rail web only) were determined. Field application over two summer seasons on an actual railway track demonstrated an average temperature reduction of 4–5℃ and a maximum of 9.7℃, particularly effective during peak solar radiation periods. Compared to conventional coatings, the fabric exhibited similar or superior thermal mitigation performance, with significantly improved reusability and maintenance convenience. A one-year outdoor exposure test confirmed minimal performance degradation (∼3 %) primarily due to UV-induced discoloration. This study is the first to provide a comprehensive and quantitative validation of detachable thermal insulation fabric for rail applications. The results suggest that this fabric-based approach offers a practical, durable, and scalable alternative to existing methods, with broader applicability to urban infrastructure, noise barriers, and steel bridge decks under thermal stress.]]></description>
      <pubDate>Mon, 29 Dec 2025 09:34:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/2616650</guid>
    </item>
    <item>
      <title>Study on the Performance of Glass Fibre in Hot Bituminous Mixes</title>
      <link>https://trid.trb.org/View/2601655</link>
      <description><![CDATA[This study is aimed at arriving the optimum dosage and study the performance of glass fibres in bituminous mixes. The Aggregates bound with bitumen are conventionally used all over the world in construction and maintenance of flexible pavements. It is thought that with the help of additives is one of the approaches to improve performance of flexible pavements. Here glass fibres have been used to improve the performance of asphalt mixtures against permanent deformation as they possess inherent compatibility with asphalt and excellent mechanical properties. The Glass fibre of different length 6 mm, 8 mm, 10 mm and 12 mm at various percentage (0.2, 0.3 and 0.4% by weight of Aggregate) were added individually to the aggregates and Marshall specimens were prepared using VG 40 Bitumen (after finding the optimum binder content) to arrive at the optimum dosage of Glass fibre in Bituminous mixes. Various performance tests were conducted to analyse the effect of Glass fibre on Bituminous mixes (i.e.,) Bituminous concrete-Grade II. In this study, it was found that the use of glass fibres in bituminous mix of length 8 mm and 0.3% by weight of aggregates with an optimum binder content of 5.73% by weight of aggregates have shown as an optimum dosage to exhibit better results than the Conventional Bituminous mix. The study compares the performance test results of Glass Fibre Bituminous mix with Conventional Bituminous mix which made from the VG-40 bitumen.]]></description>
      <pubDate>Tue, 18 Nov 2025 09:29:12 GMT</pubDate>
      <guid>https://trid.trb.org/View/2601655</guid>
    </item>
    <item>
      <title>Effect of Initial Stress Anisotropy on Small-Strain Properties of Fiber-reinforced Calcareous Sand</title>
      <link>https://trid.trb.org/View/2583378</link>
      <description><![CDATA[This research presents the effects of using glass fibers as an eco-friendly additive on the small-strain properties of calcareous sand, commonly found in coastal and land reclamation areas. A series of resonant column tests were conducted on Hormoz calcareous sand, reinforced with randomly distributed glass fibers, under isotropic and anisotropic stress conditions. The results showed that glass fibers increased the small-strain shear modulus. Moreover, with increasing confining pressure, the optimal fiber content decreased from 2% to 1% (by weight). The damping ratio slightly decreased with 2% fiber content but increased with 1%. Overall, both shear modulus and damping ratio were increased with an appropriate amount of glass fiber reinforcement. The results of all tests indicated that initial stress anisotropy increased the shear modulus. However, fiber content and initial stress anisotropy had a negligible effect on the normalized shear modulus. In this study, an empirical relationship was also proposed to estimate the ratio between the maximum shear modulus under anisotropic and isotropic stress conditions. This relationship was validated using a comprehensive laboratory dataset, and it was found to depend only on the initial stress anisotropy and to be independent of confining pressure, fiber content, particle shape, or void ratio.]]></description>
      <pubDate>Thu, 18 Sep 2025 09:47:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/2583378</guid>
    </item>
    <item>
      <title>Crashworthiness analysis of a novel steel-GFRP-foam protective structure for ECC-RC pier against vessel collision</title>
      <link>https://trid.trb.org/View/2583155</link>
      <description><![CDATA[This study aimed to develop a novel steel-glass fiber reinforced polymer (GFRP)-foam protective structure to protect engineered cementitious composite (ECC)-reinforced concrete (RC) piers against vessel collisions. Pendulum impact experiments were taken to clarify the collision protective property of this composite device. An advanced numerical model of the corresponding impact test was respectively built and verified. Moreover, the steel-GFRP-foam protective device was further applied in a prototype collision simulation between the vessel and ECC-RC bridge, and its crashworthy feasibility and design consideration were comprehensively analyzed in practical engineering. Impact experiment results displayed that this innovative structure had a certain crashworthy prospect with its outstanding steel ductility and core cushioning performance. Both a higher preliminary stiffness and unreasonable interface bonding limited the ECC application in collision protective fields. Full-scaled collision simulation results indicated that the excessive horizontal displacement, which may cause a bridge overturning or beam falling, could be effectively weakened through the installation of a steel-GFRP-foam protective structure. This finding was conducive to the displacement-based anti-collision design of ECC-RC bridge structures. Crashworthy design consideration results demonstrated that a combined method containing the orthogonal anti-collision simulation and response surface analysis could supply an optimized protective concept for the steel-GFRP-foam composite device.]]></description>
      <pubDate>Mon, 11 Aug 2025 09:12:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2583155</guid>
    </item>
  </channel>
</rss>