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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>
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      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Integrated optimization framework for fire-resilient and sustainable hybrid steel-concrete composite footbridges</title>
      <link>https://trid.trb.org/View/2696279</link>
      <description><![CDATA[While structural optimization is essential for sustainable design, its potential for complex structures to enhance resilience to extreme events remains underexplored. Hybrid steel-concrete systems offer significant performance benefits, yet their efficiency under these critical scenarios requires further investigation. This study addresses these gaps by proposing a straightforward and integrated multi-objective optimization framework that treats fire performance as a primary design driver alongside cost, environmental impact, and pedestrian comfort. The framework is demonstrated on a 20 m simply supported steel-concrete composite footbridge composed of two hybrid welded I-girders and a 3 m-wide concrete deck, with design variables defined by geometry, material strengths, and the degree of composite interaction. Results demonstrate that hybrid girders are highly effective across all scenarios, reducing total costs relative to conventional girders while maintaining comparable environmental performance. These benefits are particularly significant for designs that prioritize dynamic efficiency, where cost reductions reach up to 21% even under high comfort requirements. Optimal configurations typically employ lower-strength steel for the web and higher-strength steel for the flanges, with a yield strength ratio of around 1.6 as a practical design recommendation. Fire safety is improved with more compact girders, whereas slender geometries enhance dynamic performance, highlighting the distinct nature of these objectives. Incorporating fire performance considerations at the conceptual design stage leads to safer, more resilient, and cost-effective footbridges with minimal environmental impact. Overall, the proposed framework promotes performance-based structural design by supporting informed decision-making across multiple competing criteria and extreme conditions.]]></description>
      <pubDate>Fri, 28 Aug 2026 08:34:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2696279</guid>
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    <item>
      <title>Application of Thermochemical Modeling to Aircraft Interior Polymeric Materials II - Multilayered Seat Cushions</title>
      <link>https://trid.trb.org/View/2732477</link>
      <description><![CDATA[This report summarizes the results from a twelve-month study of applying thermochemical modeling to multilayered polymeric materials, passenger aircraft seat cushions. The use of fire-blocking layer(s) between the foam cushion and the covering fabric has been studied extensively to minimize fire hazards from aircraft seats. The objectives of this work are to expand the thermochemical model for the multilayered materials and to experimentally verify theoretical predictions. First, the thermochemical model is extended to any number of multilayered materials, by applying the same analysis technique used in the previous work. The additional constraints of temperature and heat flux continuities at every interface are also applied. A computer program is developed to predict burning behavior of seat cushion systems with and without a fire-blocking layer. Second, a series of tests burning seat cushions with and without a fire-blocking layer are conducted in a modified NBS Smoke Density Chamber. The chamber was supplemented with a multichannel recorder/multiple thermocouples and a weight-measuring device to determine temperature profile and to continuously monitor weight loss, respectively. The results indicate that the predicted temperature profiles are in very good agreement with the experimentally determined ones, and that the same effectiveness of the fire-blocking layers is predicted as that of actual weight loss measurements. It is, however, observed that the formation and presence of a void inside of the polyurethane foam seem to cause the over-prediction of the temperature profile and under-prediction of the weight loss (compared to the case when the void is small or nonexistent).]]></description>
      <pubDate>Wed, 19 Aug 2026 18:11:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2732477</guid>
    </item>
    <item>
      <title>Solid-State Thermochemistry of Flaming Combustion</title>
      <link>https://trid.trb.org/View/2742784</link>
      <description><![CDATA[The thermal and chemical processes which occur in the solid state during flaming combustion are examined. A phenomenological model of fuel generation provides the relationships between macroscopic flammability parameters and polymer chemical structure and shows how the coupling of thermal diffusion and chemical kinetics occurs naturally in the pyrolysis zone. Fire behavior and flammability of solid polymers are predicted using the ignition temperature, heat of combustion, heat of gasification, and char yield calculated from the chemical structure; and the results are compared to experimental values. The objective of this work is to develop a consistent, solid-state physical chemistry of flaming combustion which bridges the gap between fire and material sciences to help guide the discovery of new, more fire-resistant polymers.]]></description>
      <pubDate>Wed, 19 Aug 2026 11:16:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/2742784</guid>
    </item>
    <item>
      <title>Evaluation of an Improved Flame Resistant Aircraft Window System</title>
      <link>https://trid.trb.org/View/2732472</link>
      <description><![CDATA[Information was obtained by conducting a series of representative fire modeling experiments of aircraft cabin window systems employing salvaged segments of a McDonnell Douglas DC-10 aircraft. Experiments were performed in which a thermally improved window system was installed adjacent to a standard window configuration and exposed to flame impingement from a JP-4 fuel fire. The results of test 1 indicated that the thermally improved DC-10 window configuration, employing the stretched acrylic pressure pane and the new EX 112 fail-safe pane, provided an overall improvement in flame resistivity over the standard all acrylic window system of at least 79 seconds (1.3 minutes). During this experiment, the silicone rubber window gasket provided adequate thermal and mechanical stability toward preventing flame penetration into the cabin through the improved fail-safe (EX 112) window system for 225 seconds (3.75 minutes), which was the duration of fire exposure. The average failure time of the stretched acrylic and thermally improved (EX 112) fail-safe window panes in tests 2, 3, and 4 was 198 seconds (3.3 minutes) and 249 seconds (4.15 minutes), respectively, after fuel ignition. These data indicated that, on average, an improvement in fire resistivity of 51 seconds (0.85 minute) was obtained by the improved (EX 112) window configuration over the standard stretched acrylic window system. Comparative tests performed with representative DC-10 fuselage components employing the cabin interior honeycomb panel (test 3) and the aluminum panel (test 4) configurations, showed that the honeycomb panel provided a minimum improvement in flame resistivity of 67 seconds over the aluminum interior panel.]]></description>
      <pubDate>Tue, 18 Aug 2026 17:02:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2732472</guid>
    </item>
    <item>
      <title>Optimization of Aircraft Seat Cushion Fire Blocking Layers</title>
      <link>https://trid.trb.org/View/2732192</link>
      <description><![CDATA[This report describes work completed by the National Aeronautics and Space Administration - Ames Research Center under Interagency Agreement No. DTFA03-A00149 for the Federal Aviation Administration Technical Center. The purpose of this work was to examine the potential of fire blocking mechanisms for aircraft seat cushions in order to provide an optimized seat configuration with adequate fire protection and minimum weight. Aluminized thermally stable fabrics were found to provide adequate fire protection when used in conjunction with urethane foams, while maintaining minimum weight and cost penalty.]]></description>
      <pubDate>Sat, 08 Aug 2026 18:07:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2732192</guid>
    </item>
    <item>
      <title>Degradation and Characterization of Antimisting Kerosene (AMK)</title>
      <link>https://trid.trb.org/View/2714184</link>
      <description><![CDATA[Experiments are described which demonstrate the feasibility of degrading Antimisting Kerosene (AMK) in a single pass with a system consisting of a hydraulic fuel pump from a TF30 engine and several types of flow restrictors such as packed tubes or needle valves. The performance of the degraded AMK was evaluated with full-scale aircraft filters (JT8D and CF6), a T63 combustor and laboratory scale tests including filtration, ignition, and gel permeation chromatography. Rheological experiments indicated that while the shear viscosity of AMK increases above a critical shear rate, the magnitude of the shear viscosity is not large enough to explain the effectiveness of the FM-9 additive. However, it has been shown that, associated with the critical shear rate, AMK exhibits strong viscoelastic effects that are not evident at low shear rates or in flow through an orifice.]]></description>
      <pubDate>Tue, 07 Jul 2026 17:29:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2714184</guid>
    </item>
    <item>
      <title>Quantifying internal cavity effects on heat transfer in large-diameter parallel wire cables: Tests and high-fidelity simulations</title>
      <link>https://trid.trb.org/View/2709238</link>
      <description><![CDATA[Accurate prediction of temperature fields in parallel wire cables—critical components like main cables, hangers, and stay cables in cable-supported bridges—is pivotal for their fire resistance assessment. However, existing studies predominantly focus on small-scale cables and rely on oversimplified homogeneous models that neglect internal cavities, undermining reliability for large-scale applications. Addressing this gap, this study investigates sectional heat transfer characteristics of large-diameter (100–340 mm) parallel wire cables with explicit consideration of internal cavities. Temperature rise tests were conducted to capture wire temperature histories at different cross-sectional positions, followed by the development of a refined numerical model incorporating cavity structures, validated using experimental data. The effects of fire source models, cable porosity, and diameter on heat transfer were analyzed. Results show numerical-experimental discrepancies ≤ 35℃ within 60 min and ≤ 10% thereafter, confirming model reliability. Internal cavities induce uneven temperature distributions, influenced by fire source, porosity, and diameter. HC fire causes peak temperatures of 1035℃ and gradients of 445℃, with the time to reach the peak values being 48 min and 12 min, respectively. That is, HC fire poses the greatest threat to cable components, and it is recommended as the fire source model for fire resistance analysis of cable components. Marked differences exist between homogeneous round steel and actual cables (357℃ in internal wire temperature, 402℃ in gradient), underscoring the necessity of cavity-aware modeling. The research provides reliable temperature rise data for evaluating fire-induced bearing capacity degradation and optimizing fire protection design of cable components.]]></description>
      <pubDate>Tue, 23 Jun 2026 13:50:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/2709238</guid>
    </item>
    <item>
      <title>Influence of Liquid Water and Water Vapor on Antimisting Kerosene (AMK)</title>
      <link>https://trid.trb.org/View/2709439</link>
      <description><![CDATA[Experiments have been performed to evaluate the compatibility of liquid water and water vapor with antimisting kerosenes (AMK) containing polymer additive FM-9 developed by Imperial Chemical Industries. This effort consists of the determination of water solubility in AMK, influence of water on restoration (degradation) of AMK, and effect of water on standard AMK quality control methods. The principal conclusions of this investigation are: 1) The uptake of water in AMK critically depends upon the degree of agitation and can be as high as 1300 ppm at 20°C; 2) More than 250 to 300 ppm of water in AMK causes an insoluble second phase to form. The amount of this second phase depends on fuel temperature, agitation, degree of restoration (degradation) and the water content of the fuel; 3) Laboratory-scale experiments indicate precipitate formation when water vapor comes in contact with cold fuel surfaces at a much lower level of water (125 to 150 ppm); 4) Precipitate formation is very pronounced in these experiments where humid air is percolated through a cold fuel (-20°C); 5) Laboratory tests further indicate that water droplet settling time is markedly reduced in AMK as compared to Jet A; 6) Limited low temperature testing down to -30°C under laboratory conditions indicates the formation of stable, transparent gels; 7) The antimisting (fire protection) properties of AMK in the presence of water are equivalent to or better than in its absence; and 8) the present AMK quality control methods (filter and cup tests) are influenced by the variation of water content in AMK.]]></description>
      <pubDate>Tue, 23 Jun 2026 11:09:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2709439</guid>
    </item>
    <item>
      <title>Frictional Characteristics and Heat Transfer of Antimisting Fuel in Tubes</title>
      <link>https://trid.trb.org/View/2709436</link>
      <description><![CDATA[Experiments have been performed to determine the skin friction and heat transfer behavior of antimisting kerosene (AMK) in pipe flows. The additive used in the AMK was FM-9 developed by Imperial Chemical Industries. AMK has been developed as an aviation safety fuel to reduce post-crash fires. The principal aim of the present investigation was to determine the modification in flow and heat transfer behavior caused by the presence of the antimisting polymer additive in jet fuel. The present study indicates that the AMK skin friction versus Reynolds number, or Nusselt number versus Reynolds number behavior, can be divided into three regions: (1) Newtonian laminar region, (2) shear-thickening transition region, and (3) drag­-reducing turbulent region. At low flow rates, AMK has Newtonian behavior, i.e. constant viscosity. At a certain critical wall shear rate which depends on the fuel temperature and additive concentration, shear thickening occurs and causes a large increase in skin friction and heat transfer rates. In the third region, the skin friction and heat transfer rates drop rapidly and fall below the predicted Newtonian flow skin friction and heat transfer values; e.g., for 0.3 percent FM-9 AMK at a temperature of 20°C, these values coincide with Newtonian values at solvent Reynolds number, Res, equal to 2.2 x 10⁴ and 1.0 x 10⁴. Beyond these points, there is a reduction in skin friction and heat transfer rates.]]></description>
      <pubDate>Mon, 22 Jun 2026 12:22:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2709436</guid>
    </item>
    <item>
      <title>Degradation and Characterization of Antimisting Kerosene (AMK)</title>
      <link>https://trid.trb.org/View/2705403</link>
      <description><![CDATA[The effect of elongational flow on polymer degradation has been studied by forcing antimisting kerosene (AMK) through metal screens and packed tubes at high velocities. Effects of screen size, bead size, and tube length on degrader power have been determined. At a specific power of 15 kWs/liter (30 HP at 10,000 lb/hr), AMK exhibits filtration and ignition properties similar to Jet A in small-scale tests. A glycol/amine carrier fluid that was originally developed to promote rapid dissolution of FM-9 polymer in Jet A has been found to increase antimisting effectiveness, reduce gel formation and filtration resistance, and require less degrader power. Other fuel-soluble hydrogen bonding agents have been found to produce similar effects with FM-9 in Jet A. At low Reynolds numbers, the flow of AMK through metal screens and paper filters is characterized by a critical velocity that depends on polymer degradation, filter material, pore size, and presence of hydrogen bonding agents. Below this critical velocity, the flow resistance of AMK is determined by the low shear viscosity which is only 1.6 times higher than Jet A. At a slightly higher velocity, the flow resistance increases dramatically. While this phenomenon is commonly observed with many polymer solutions, in the case of FM-9 it is also associated with gel formation that may result in filter plugging. However, at very high velocities, gel formation and filter plugging are no longer evident with either metal screens or packed tubes.]]></description>
      <pubDate>Tue, 16 Jun 2026 14:10:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/2705403</guid>
    </item>
    <item>
      <title>Wing Spillage Tests Using Antimisting Fuel</title>
      <link>https://trid.trb.org/View/2703712</link>
      <description><![CDATA[Fuel spillage tests were conducted to evaluate the performance of an antimisting fuel (FM-9 with glycol/amine carrier fluid) in a simulated crash environment. The results of the tests are: (1) FM-9 when compared with neat Jet A afforded flammability protection even under test conditions which resulted in a "fail" for the FM-9; (2) 0.3% 80°F FM-9 provided excellent fire resistance at air-shearing velocities up to 125 knots; (3) spillage rates from 20 to 60 gallons per second yielded similar results; (4) fuel temperature impacted the antimisting performance of the fuel, 47°F fuel and 110°F fuel provided fire resistance at air-shearing velocities of 133 and 116 knots, respectively; (5) additive concentration affected fire resistance performance with 0.2 percent and 0.35 percent providing protection at air-shearing velocities of 99 knots and 142 knots, respectively; (6) MK40 rockets used as an ignition source did not alter the basic fire resistance properties of the fuel; (7) the height above the ground of the fuel release point did not affect the test results; (8) the discharge orifice shape did not affect the tests results; (9) engine fuel ingestion tests indicated that fuel quantity ingested was the governing factor as to whether engine surge occurs; (10) deceleration tests indicated that the safety range of FM-9 is about 30 knots higher in deceleration tests versus steady-state spillage tests.]]></description>
      <pubDate>Mon, 15 Jun 2026 17:09:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2703712</guid>
    </item>
    <item>
      <title>Development of a Next-Generation Burner for Use in Testing Thermal Acoustic Insulation Burnthrough Resistance</title>
      <link>https://trid.trb.org/View/2696957</link>
      <description><![CDATA[A new and improved burner was developed to test the fire penetration resistance of thermal acoustic insulation in accordance with Title 14 Code of Federal Regulations (CFR) Part 25.856 (b). This next-generation (NexGen) burner was developed mainly to provide industry with an alternative to the currently accepted burner apparatus manufactured by Park Electric Motors of Atlantic City, NJ. Title 14 CFR 25.856 was written based on the use of the Park DPL 3400 burner; however, the company stopped production of this apparatus shortly after the new test method became final in 2003. The NexGen burner can be considered a direct replacement to the Park-manufactured burner, with several key improvements. The NexGen burner is based on the same operating principle as the Park DPL 3400, using the same, or very similar, internal components to avoid drastically changing the overall character of the flame. The main difference is the elimination of the electric motor, which provided power to the fuel pump and blower fan in the Park-manufactured burner. In the NexGen burner, these functions have been replaced with regulated and conditioned compressed air and a pressurized fuel delivery system. Compressed air, when metered with a sonic orifice and conditioned to remove heat and moisture, proves to be more consistent over extended periods of time than to using a shaft-driven blower and laboratory air for the burner, thus increasing the repeatability of the NexGen burner. NexGen fuel delivery is provided by applying a head pressure of nitrogen gas on liquid fuel contained in a pressure vessel. This new method eliminates any fluctuations that were previously experienced with the electric motor and shaft-driven fuel pump typical of the Park-manufactured burner. The exit air velocity and the fuel flow rate of the NexGen burner were matched to that of the Park DPL 3400 burner specifications to produce a flame of similar temperature and heat flux. Initial comparison tests indicated that the NexGen burner provides burnthrough results similar to that of the Park burner when comparing identical materials. Multiple NexGen burners were produced, and all were proven to provide the same results. NexGen burners were shipped to participating laboratories, tested with identical materials, and proven to be reproducible at different locations. This work has shown that an equivalent burner can be fabricated from readily available materials and can be used to test materials according 14 CFR 25.856 (b).]]></description>
      <pubDate>Sat, 23 May 2026 18:35:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2696957</guid>
    </item>
    <item>
      <title>Evaluation of the 12-Second Vertical Bunsen Burner Test Used to Determine the Fireworthiness of Aircraft Duct Materials</title>
      <link>https://trid.trb.org/View/2693737</link>
      <description><![CDATA[This technical note provides the technical approach and test results of the evaluation of the currently used Federal Aviation Administration certification test, known as the 12-second vertical Bunsen burner test, to certify aircraft ducts and conduits.]]></description>
      <pubDate>Sun, 26 Apr 2026 17:38:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2693737</guid>
    </item>
    <item>
      <title>A Comprehensive Guideline for GDOT Bridges Fire Hazard Assessment</title>
      <link>https://trid.trb.org/View/2681206</link>
      <description><![CDATA[Bridge fires can cause rapid and severe loss of structural capacity. This loss of capacity often leads to major safety risks, network disruptions, and high economic impacts. A curated history of United States bridge fires in the 20th and 21st centuries is presented. This history identifies recurring ignition sources, contributing factors, and damage patterns associated with bridge fires. The research team further synthesizes current knowledge on critical temperatures and heat-induced defects in steel and concrete. They evaluate rapid nondestructive testing (NDT) methods that can be used for a post-fire triage inspection. Integrating the historical case studies, common trends found in the historical record of bridge fires, material behavior, and NDT information, the team presents practical guidance to support post-fire triage of highway bridges. In addition, they propose a methodology that may be implemented to develop a single, easy-to-use universal model to determine the residual structural capacity of fire damaged concrete. Laboratory burn testing of concrete samples was conducted to quantify residual compressive strength as a function of changes in rebound hammer values and ultrasonic pulse velocity. During testing, the model produced a standard error of 8 percent for estimating residual compressive strength. This indicates promise for refinement with further testing. A three-factor model that incorporated visual cues was also developed. The three-factor model improved overall fit but raised concerns about robustness and practical reliability. The report concludes with recommendations for post-fire inspection procedures, expanded training for bridge and maintenance personnel, and wider availability of NDT equipment to support timely, consistent, and defensible triage decision following bridge fires.]]></description>
      <pubDate>Thu, 19 Mar 2026 08:56:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2681206</guid>
    </item>
    <item>
      <title>Experimental Evaluation of Fire Resistance and Postfire Mechanical Behavior of Cables with Multiple Fire Protection Strategies</title>
      <link>https://trid.trb.org/View/2668461</link>
      <description><![CDATA[As critical components of cable-supported bridges, bridge cables face significant threats from elevated temperatures induced by fire accidents. This study developed a specialized fire-furnace test to evaluate the postfire performance of eight specimens, including five 109-strand and three 55-strand cable specimens, combining elevated temperature and stress. During the eight fire-furnace tests, heating duration, cable diameter, and fire resistance measures were systematically considered. Having finished fire-furnace tests and been cooled naturally to ambient temperature, tensile and fatigue tests were performed to assess the residual mechanical properties of the cables. Test results indicate that combustion of the polyethylene (PE) sheath significantly accelerates heat transfer to the outer steel wires, leading to a rapid temperature rise and greater temperature difference across the cable cross section. This thermal effect contributes to more severe structural damage, demonstrating that PE is not a suitable material for fire protection in cable systems. Mechanical performance tests conducted after high-temperature exposure revealed that the elastic modulus remains nearly unchanged when the peak temperature is below 600°C but exhibits a sharp reduction once the temperature exceeds 600°C. However, the yield and ultimate strength decrease to approximately 22% and 31% of their initial values, respectively, until the average temperature arrived at 800°C, and then grow to around 25% and 35% as the temperature continues to rise to 920°C. In addition, the fatigue life reduces at least 75% of the initial value as the temperature grows to around 600°C. Ceramic fiber tape with thicknesses of 6 and 3 mm has been recommended as one of the most effective fire resistance measures for specimens with 109 and 55 steel wires, as they can control the temperature rise with higher efficiency.]]></description>
      <pubDate>Wed, 18 Mar 2026 09:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2668461</guid>
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