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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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    <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>
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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>3D Printed Injection Molding Tool: An Unique Approach for New Product Development</title>
      <link>https://trid.trb.org/View/2624060</link>
      <description><![CDATA[Automotive industry frequently uses 3D printed plastic proto parts during new product development phases as it bypasses the high tooling investment & development time at early part development stage. However, for some application, 3D printing technique & its limited material options are not fulfilling the required material properties in the part, resulting poor performance during product testing which may mislead the design engineer during validation process.To overcome this, we introduce a novel approach in constructing injection molding tool by 3D printing the core and cavity using Stereolithography (SLA). This enables production of parts with application-recommended material grades, facilitating traditional validation and increasing stakeholder confidence.This paper compares part quality from 3D printed molds against conventional metallic molds for a shifter gear housing cover, demonstrating a 45% reduction in tooling costs and a 75% decrease in tooling development time. Mold life analysis using PP Glass Filled 30% (PPGF30) and Nylon 66 Glass Filled 30% (Nylon 66GF30) yielded approximately 100 and 25 parts, respectively. We also discussed the challenges encountered during the mold 3D printing and injection molding process. This innovative technique offers broad applicability across plastic part manufacturing industries.]]></description>
      <pubDate>Thu, 13 Nov 2025 16:07:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2624060</guid>
    </item>
    <item>
      <title>Brittle or Ductile? Effects of Print Orientation and Raster Angle on Polylactic Acid (PLA) Fused Filament Fabrication (FFF) Tensile Samples</title>
      <link>https://trid.trb.org/View/2539314</link>
      <description><![CDATA[The automotive industry leverages Fused Filament Fabrication (FFF) -based Additive Manufacturing (AM) to reduce lead time and costs for prototypes, rapid tooling, and low-volume customized designs. This paper examines the impact of print orientation and raster angle on the tensile properties of Polylactic Acid (PLA), selected for its ease of use and accessibility. Dog bone samples were designed to the ASTM D638 tensile testing standard and printed solid with a 0.2 mm layer height, two outer walls, and varying raster-fill angles, with layers alternating by 90°. Testing was conducted on the MTS Criterion Model 43, 50 kN system. Varying print orientation along the X and Y axes (double angle builds) produced a Young's modulus (YM) range of 0.7519, reflecting a 34.42% increase between the witnessed minimum and maximum values. These builds exhibited more brittle behavior than most single angle builds, except for X10 Y10 Z0 at a 45° raster (the lowest recorded YM) and X0 Y15 Z0 at a 30° raster (the highest recorded YM). The same build orientation (X0 Y15 Z0) with varying raster angles between 0°-90° resulted in a yield stress range between 2.53 and 3.31 kN/mm2. These findings show that strategic build parameter configuration enables PLA to exhibit both flexible and rigid characteristics. Therefore, when creating AM solutions, Design for Additive Manufacturing (DfAM) and material selection are important, but slicing parameters also play a crucial role in determining a part's final mechanical properties. These findings lay the groundwork for applying this experiment methodology to other thermoplastics commonly used in the automotive industry, such as ABS and Nylons. This research aims to provide detailed experimental data, highlighting extreme values and uncertainties in the tensile strength of FFF samples. Understanding how build orientation influences part strength can help engineers optimize performance and predict failure modes.]]></description>
      <pubDate>Tue, 15 Apr 2025 13:56:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2539314</guid>
    </item>
    <item>
      <title>Development of the Xterra® Luggage-rack System from Nissan with ASA/PC Weatherable Resin</title>
      <link>https://trid.trb.org/View/1787455</link>
      <description><![CDATA[The luggage-rack-system market has historically been dominated by nylon- (polyamide)-based resins. The recent design and development of the Xterra® luggage rack system (LRS) from Nissan represents a new trend in luggage-rack system design. Nissan utilized an ASA/PC weatherable thermoplastic resin to develop its special gray, molded-in-color luggage-rack components. The balance of weathering performance and physical properties that ASA/PC resin offers allowed the automaker to design these structural components and avoid the high cost of paint. This paper discusses the design and development of the luggage-rack system as well as the process utilized to evaluate ASA/PC resin for performance in static loading, heat resistance, vibration performance, etc. Furthermore, the paper explores how ASA/PC resin parts might be designed in for future luggage-rack-system applications.]]></description>
      <pubDate>Tue, 28 Jan 2025 14:52:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/1787455</guid>
    </item>
    <item>
      <title>Selecting Nylon-Based Plastics for Laser Welding Technology</title>
      <link>https://trid.trb.org/View/1787504</link>
      <description><![CDATA[Selecting thermoplastics for welded, under-the-hood, automotive parts strongly depends on the plastic material properties, part design, as well as the molding and joining / welding technology conditions. Laser transmission welding (LTW) requires preferential deposition of energy and subsequent melting and diffusion of the material in the interfacial / weld-plane zone. This is optimized when the laser beam is transmitted through the thermoplastic transparent part and absorbed by the adjoining part to be welded. Energy deposition can be controlled to some extent by adjusting laser power, choice of beam focussing optics, sweep rate, etc. The thermoplastic material properties and composition (reinforcements, fillers, additives, pigments, etc.) may have the greater influence and need to be characterized for optimum material selection for the transmission welding application. Commercial nylon based thermoplastics cover a large array of compositions, which may affect the laser transmission welding (LTW) process. To provide a guide to nylon based thermoplastics selection for these applications the authors have evaluated the influence of specific material composition factors and properties, such as fiber-glass, mineral filler, impact modifier content, and color / pigment version on the Near InfraRed (NIR) transmission characteristics, including the laser wavelength (1.06 mm). They have related these findings to the mechanical performance of nylon welded joints in terms of the influence of transmission laser welding technology parameters (laser power, welding speed, laser beam spot diameter, clamp pressure, etc.) and thermoplastic composition (reinforcements, fillers, additives, pigments, etc.). Comprehensive results of this evaluation will assist plastic parts designers and technologists in selecting nylon based thermoplastics and developing new products using laser transmission welding (LTW) technology.]]></description>
      <pubDate>Wed, 22 Jan 2025 09:33:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/1787504</guid>
    </item>
    <item>
      <title>100% Post-Consumer Recycled Nylon 6: Repolymerized Resin Provides Full Mechanical, Physical, &amp; Aesthetic Properties</title>
      <link>https://trid.trb.org/View/1787471</link>
      <description><![CDATA[The increased use of recycled resins can create a dilemma for automotive designers. On the one hand, there is a growing initiative to increase recycled materials content on vehicles, globally. On the other hand, traditional methods of recycling polymeric materials -both thermoplastics and thermosets - can lead to degradation of engineering, mechanical, processing, and / or aesthetic properties of the resin. In an era where quality rules, this situation forces designers to accept a much lower percentage of recyclate than they might otherwise wish to use or risk unacceptable property loss in molded parts - something no automaker can “afford ” for long. Hence, a valuable feedstream of materials (polymers) often ends up destined for a landfill once many consumer products are broken down and more easily reusable or recyclable materials are salvaged. As a case in point, each passenger car built globally contains an average of 15 - 20 kg of nylon polymers. Because of the excellent performance characteristics of this family of engineering thermoplastics, nylon polymers would be attractive candidates for reuse on vehicles: If there were a way to reduce or prevent property loss during reclamation and reprocessing, and; If automakers and their suppliers could secure a ready supply of this recycled resin. Fortunately, a new technology breakthrough now makes it possible to meet both of these goals, at least for nylon 6 resins. Using waste nylon 6 carpet as feedstock - with the option of accepting painted or unpainted, pigmented or unpigmented nylon 6 parts from other industries, including automotive - the patented process first breaks nylon 6 down to its monomer, caprolactam. The recycled caprolactam is then repolymerized back into new “virgin ” nylon 6 resin that can be further modified with fillers, colorants, and additives to create resins that are indistinguishable from those made from conventional “virgin ” caprolactam feedstock. This paper briefly discusses the nylon 6 repolymerization process, with emphasis on the kinds of applications these materials can be used for, and then speculates on the potential impact of this technology on closed-loop recycling programs in the automotive industry.]]></description>
      <pubDate>Thu, 16 Jan 2025 09:09:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1787471</guid>
    </item>
    <item>
      <title>Recycle Solutions That Make Environmental, Economic $en$e</title>
      <link>https://trid.trb.org/View/1786870</link>
      <description><![CDATA[The Auto Industry has clearly defined itself a role in environmental stewardship and challenged the supply chain to support the stewardship with the objective of avoiding landfills. At the same time challenges remain: Collection, identification and sorting; Processing waste streams into reusable raw materials; and Convincing the industry supply chain that these raw materials will not negatively impact supply, product reliability and cost. This paper will address how DuPont is facing these challenges in concert with its customers in the automotive supply chain. It will focus on several key technologies applied to polyester (PET), nylon 6 and nylon 66: The traditional mechanical recycling technology; and The innovative chemical recycling technology.]]></description>
      <pubDate>Thu, 07 Nov 2024 11:52:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/1786870</guid>
    </item>
    <item>
      <title>Development of All-Nylon Charge Air Cooler for Automotive Applications</title>
      <link>https://trid.trb.org/View/1790840</link>
      <description><![CDATA[The preliminary experimental results of an all-nylon charge air cooler development for automotive application are presented. The results achieved during the project deployment in terms of performance comparison between metal and nylon Charge air Coolers are reported. Data related to both bench and road tests are presented and discussed.]]></description>
      <pubDate>Tue, 19 Dec 2023 17:03:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/1790840</guid>
    </item>
    <item>
      <title>Characterization and modelling of the dynamic stiffness of nylon mooring rope for floating wind turbines</title>
      <link>https://trid.trb.org/View/2254029</link>
      <description><![CDATA[Nylon is a very promising candidate to replace steel chain moorings for Marine Renewable Energies applications like Wave Energy Converters or Floating Wind Turbine in shallow-water. However, test data for nylon ropes in a wet environment at intermediate scales are lacking in the literature except in a recent study by Sørum et al 2022. This article proposes a new set of experimental data on nylon subropes with a detailed test procedure. This work focuses on the dynamic stiffness of nylon mooring line and its experimental evaluation at realistic orders of mean load, load variation and frequency. The authors also examine the accumulated strain after successive test procedures. The experimental campaign highlights the stiffness non-linearity with respect to both the mean tension and amplitude. A simple bi-linear model taken from the work of Huntley 2016; Pham 2019 is considered here, and is shown to provide a good simulation of the experimental results.]]></description>
      <pubDate>Tue, 03 Oct 2023 14:31:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2254029</guid>
    </item>
    <item>
      <title>NSF (Nylon Synthetic Fiber) Effectiveness in Stabilizing Weak Subgrade Soil: An Experimental Investigation</title>
      <link>https://trid.trb.org/View/2194387</link>
      <description><![CDATA[Improvement in subgrade soil has always been an area of concern for highway and geotechnical engineers. Weak subgrade soil results in a greater thickness of the pavement layer, which increases the cost of pavement construction. It further leads to large deformations, which in turn cause continuous deterioration of the paved surface. To solve this problem, various engineering solutions and soil improvement mechanisms were previously proposed. This study was designed to investigate the stabilization of weak subgrade soil with nylon synthetic fiber (NSF) in a compromising combination. Previously, some investigations used a lower fiber content with a higher fiber length, whereas others used a lower fiber length with a higher fiber content. However, this investigation was uniquely designed to stabilize weak subgrade soil with the consideration of appropriate fiber length (10 mm and 20 mm) and content (0.5%, 1%, 1.5%, and 2.5%). The engineering properties of the soil, the effect of NSF on weak subgrade soil, various fiber content and aspect ratios, and the optimum content and critical fiber aspect ratio were investigated in a laboratory. The effect of fibers on compaction, CBR values, and CBR swell values has also been studied. Laboratory results on the modified compaction tests showed that maximum dry density (MDD) was increased with the increment of fiber content, whereas optimum moisture content (OMC) remained constant. The soaked CBR and CBR swell values of natural soil were 1.80% and 8.95%, respectively. Due to reinforcement, the percentage increase in soaked CBR value at the optimum NSF content is 265.3, 310.0, 282.8, and 342.2 for aspect ratios of 33.33, 66.67, 25, and 50, respectively, with reference to natural soil. Also, the percentage decrease in swelling is 34.7, 52.75, 43.55, and 36.9, respectively. Moreover, the CBR value increases with the increase in aspect ratio by keeping the diameter constant and decreases with the increase in aspect ratio by keeping the length constant. It was also observed that increasing the length and diameter of NSF further increased the CBR value of reinforced soil. This increment was substantial at a fiber content of 1.5% for an aspect ratio of 50 (length = 20 mm, diameter = 0.4 mm). There was also a decrease in the CBR swelling value with an increase in fiber content. Finally, this investigation concluded that the use of NSF is a solution to weak soils with regard to moisture and performance problems.]]></description>
      <pubDate>Tue, 20 Jun 2023 10:09:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2194387</guid>
    </item>
    <item>
      <title>A comparison of anchor loads, planar displacement, and rotation for nylon and polyester moored systems for a 15 MW floating wind turbine in shallow water</title>
      <link>https://trid.trb.org/View/2173913</link>
      <description><![CDATA[Renewable energy is crucial for addressing energy security and climate change challenges. Offshore wind energy presents a significant opportunity to generate renewable energy. Shallow water areas, between 50 and 70 m deep, are economically feasible for wind farms using shared anchor concepts and mooring line systems. However, choosing the appropriate type of system is critical. Previous studies have demonstrated that synthetic fiber ropes are more efficient than traditional chain catenary. In this paper the authors present the results of a dynamic analysis of a 15 MW Turbine and the VolturnUS-S reference platform deployed in the Celtic Sea. The authors compare the planar displacements, rotations, and loads acting on a shared anchor using nylon and polyester ropes, the latter as retrieved from the literature. An engineering procedure is used to simulate the behavior of the nylon rope, and a diffraction analysis is employed considering the stiffness of the mooring matrix. The authors' results show that using nylon rope reduces the peak resolved anchor load by 44% compared to polyester, but at the cost of a relatively larger displacements and rotations, which can be mitigated with improvements in mooring design. Since nylon is 10% cheaper than polyester rope with an identical minimum breaking load (MBL), and more cost-efficient anchor concepts are being investigated, the findings of this study encourage further research on nylon applications for wind farms in shallow water using shared anchors.]]></description>
      <pubDate>Tue, 23 May 2023 10:09:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2173913</guid>
    </item>
    <item>
      <title>Assessment of nylon versus polyester ropes for mooring of floating wind turbines</title>
      <link>https://trid.trb.org/View/2146296</link>
      <description><![CDATA[With the development of floating wind turbines comes the need for mooring systems suitable for shallow water depths. Compliance becomes challenging for mooring systems composed of chain and wire rope. Polyester ropes can improve compliance, but the even lower stiffness of nylon may further reduce mooring line loads. However, fatigue lifetime of nylon ropes has been limiting. This paper presents results of stiffness and fatigue tests on long lay polyester and nylon ropes and evaluates the performance of two mooring systems for a floating wind turbine. The fibre ropes’ complex stiffness behaviour is modelled by the Syrope model, with mooring analyses based on fully coupled time-domain simulations. Nylon ropes reduce the dynamic loads in the mooring system, particularly wave frequency loads. This improves the fatigue lifetime of all components, allowing a reduction of the chain cross-section area by ∼40% compared to the polyester-based mooring system. The long lay nylon ropes show excellent fatigue properties. With the reduced loading, the lifetime is longer for the nylon ropes than the polyester ropes. Ultimate loads are also reduced when using nylon, allowing reduction of the breaking load by ∼30%. This gives a thinner and lighter rope than the equivalent polyester rope.]]></description>
      <pubDate>Fri, 21 Apr 2023 09:49:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/2146296</guid>
    </item>
    <item>
      <title>High Performance Polyamides in Demanding Automotive Thermal Management Applications</title>
      <link>https://trid.trb.org/View/1806581</link>
      <description><![CDATA[High Performance Polyamides (HPPA) represent a fast-growing family of polymers, with broad applicability in demanding applications where traditional materials such as nylon 66 are not suitable. This paper reviews the basic chemistry of the nylon product family, demonstrates how the HPPA family differs from standard nylon with a focus on semi-aromatic nylons known as polyphthalamides (PPA). The authors will demonstrate how PPA is an excellent candidate for thermal management applications where traditional polyamides are not suitable via specific performance data measured at the lab scale, along with commercial applications that provide validation of HPPA use.]]></description>
      <pubDate>Wed, 28 Dec 2022 16:12:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/1806581</guid>
    </item>
    <item>
      <title>Evaluation of Optimum Fiber Length in Fiber-Reinforced Asphalt Concrete</title>
      <link>https://trid.trb.org/View/1903867</link>
      <description><![CDATA[Cracking is one of the most common distresses in asphalt pavement. Because asphalt concrete is relatively weak in tension, synthetic fibers have shown to increase its tensile strength and, therefore, reduce the chance of cracking. An approach was used in this study with the aim of evaluating the interaction between fibers and asphalt mastic and the fiber distribution in asphalt concrete. Three types of aramid fibers and two types of nylon fibers were used. A pullout test was used to determine the typical shear bond strength between fibers and the asphalt mastic. The bond strength obtained from the pullout test was then used to calculate the minimum fiber embedded length on each side of the crack in order for the fiber to reach its full capacity before being pulled out. Of course, increasing fiber length increases the chance of bridging cracks considering the random distribution of fibers in fiber-reinforced asphalt concrete (FRAC) and the random orientation of fibers relative to cracks. On the other hand, increasing fiber length may result in uneven distribution of fibers in the FRAC. Fiber extraction and recovery tests were then used to determine the dispersion of aramid fibers in the FRAC with different fiber lengths. The study showed that aramid fibers in the order of 20 mm would provide a good bond with the asphalt mastic and result in reasonable dispersion in the FRAC. The uniaxial fatigue test and flow number test were also performed on FRAC with different aramid fiber lengths. The 19-mm fibers also showed better performance test results than the 10- and 38-mm fibers. A similar length is recommended for the Nylon 1 fibers based on the bond properties only. Longer Nylon 2 fibers are recommended, but caution needs to be taken to avoid uneven fiber dispersion in the FRAC.]]></description>
      <pubDate>Fri, 28 Jan 2022 09:16:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/1903867</guid>
    </item>
    <item>
      <title>The waste transparent nylon modified bitumen properties: Experimental assessment on physical, rheological properties and storage stability</title>
      <link>https://trid.trb.org/View/1873660</link>
      <description><![CDATA[The populations consume considerable amount of plastic based materials and accordingly the waste of them increases on daily basis. It is possible to recycle plastic waste with using different technological processes that require excellent energy, cost, labor, and produce significant amount of greenhouse gas. However, the reverse of this situation can also be possible. Using the waste as a modifier in bitumen to improve their characteristics may be an eco-friendly and cost-effective alternative method for recycling. In this regard, this study was established on investigation the effect of Waste Transparent Nylon (WTN) with different rate from 0.5% to 3.0% by weight in bitumen with 0.5% increment to be used a modifier for sustainable recycling. To achieve it, series physical and rheological test were performed on the bitumen samples to determine the changes occur in properties of them. Physical test methods including penetration, softening point, viscosity and flashing point were conducted on the unaged samples. On the other hand, rheological test methods including dynamic shear resistance and bending beam rheometer tests were performed on the unaged and aged samples. To determine compatibility between the WTN and bitumen, storage stability tests were conducted. Testing results showed that modifying bitumen with WTN changes bitumen characteristics, significantly. It was found that there are certain increase in softening point, viscosity and flashing point, while decrease in penetration values. Rheological assessment, on the other hand, indicated that there are obvious increase in rutting and thermal cracking resistance, while reduce in fatigue resistance of the bitumen sample. However, WTN modified bitumen samples did not show storage stability except of the one done with 0.5%. Overall, the results pointed out that bitumen modification with WTN can be one of sustainable solution for both recycling of WTN and improvement of bitumen properties. While it is used in bitumen, certain benefits to economy and environment can be achieved]]></description>
      <pubDate>Thu, 30 Sep 2021 09:31:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/1873660</guid>
    </item>
    <item>
      <title>Experimental evaluation of the dynamic stiffness of synthetic fibre mooring ropes</title>
      <link>https://trid.trb.org/View/1855391</link>
      <description><![CDATA[Model tests are conducted to study nonlinear mechanical characteristics of nylon, polyester and high modulus polyethylene. Static tensile and cyclic loading tests are carried out to study the static and dynamic stiffness respectively. Cyclic loading tests with different mean loads and load amplitudes are designed to study the influence of these two parameters on the dynamic stiffness. Based on the measured static results, the fitted expressions for tension-elongation relations of fibre ropes are presented. The empirical expressions developed in previous studies are applied to estimate the dynamic stiffness of synthetic fibre ropes tested in this work, and the estimations are compared with the measured ones. The empirical expression used in this study aims to capture evolution of synthetic rope dynamic stiffness. The extended Kalman filter is applied to identify the parameters of the proposed empirical expressions. The performance of the extended Kalman filter in the parameter identification of the empirical expression for dynamic stiffness is discussed. Furthermore, the influences of observation uncertainties and noise on the outputs of the extended Kalman filter are checked. It is concluded that the extended Kalman filter is able to present reliable and accurate estimations to the parameters of empirical expression for systematic rope dynamic stiffness.]]></description>
      <pubDate>Thu, 01 Jul 2021 09:25:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/1855391</guid>
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