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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>
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    <item>
      <title>Mechanistic investigation of SBS modified asphalt/polyamide hybrid binders: Role of crystallization and binder-filler interaction</title>
      <link>https://trid.trb.org/View/2600870</link>
      <description><![CDATA[Low-molecular-weight polyamide (PA) is a potential binder for asphalt mixtures, but the effects of PA crystallization and binder-filler interactions on mixture properties remain unclear. This study investigates asphalt mixtures using styrene-butadiene-styrene triblock copolymer (SBS) modified asphalt/PA hybrid binders with varying penetration and binder contents. It was found that the relationship between mixture performance and binder properties or content deviates from conventional expectations, while a strong correlation exists between the properties of mastics and mixtures. To explore the underlying mechanisms, the interaction between PA and filler was analyzed using Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), while PA crystallization behavior was characterized by differential scanning calorimeter (DSC) and scanning electron microscope (SEM). The results indicate that the interactions between PA and fillers are predominantly physical, with no evidence of chemical bonding. Hybrid binder mastics exhibit a distinctive "leather-state" below 88 °C, characterized by a high modulus and low phase angle, attributed to PA crystallization of. However, this "leather-state" is absent in hybrid binders due to the greater dominance of the PA phase in mastics compared to binders. The semi-crystalline nature of PA results in stronger cohesion than the amorphous SBS modified asphalt, making SBS modified asphalt more readily absorbed by the filler than PA. These findings provide new insights into the mechanistic behavior of hybrid binders, emphasizing the critical role of PA crystallization in performance optimization.]]></description>
      <pubDate>Thu, 30 Oct 2025 08:49:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2600870</guid>
    </item>
    <item>
      <title>Aging resistance in model bio-based binders for road materials: a study of rosin esters and vegetable oil combinations</title>
      <link>https://trid.trb.org/View/2556810</link>
      <description><![CDATA[Bio-based binders offer a potential solution for the availability issues of bitumen, though their aging behaviour may differ mainly due to higher oxygen content. This study aims to understand the aging resistance of model bio-based binders produced from various vegetable oils (palm, linseed, sunflower, olive) and rosin esters (Rosin A, B, C). A commercial bio-based binder was used for comparison and design. FTIR-ATR show no differences through lab aging, while DSR results reveal varying impacts after lab aging. The types of rosin esters and vegetable oils significantly affect aging resistance. Although the specific chemical characteristics of the rosin esters influencing aging remain unclear, a strong correlation exists between the iodine numbers of vegetable oils, indicating that oils with iodine numbers higher than 150 are unsuitable for bio-based binders. This paper provides useful information about bio-based binder component properties helping at developing materials that resist aging.]]></description>
      <pubDate>Thu, 26 Jun 2025 11:42:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/2556810</guid>
    </item>
    <item>
      <title>Unique Correlation Between Binder, Mastic, and Mixture: A Multi-Scale Investigation of Novel Asphalt Hybridized with Polyamide Resin</title>
      <link>https://trid.trb.org/View/2537713</link>
      <description><![CDATA[Asphalt mixtures with binders hybridizing with polyamide (PA) resin exhibited ultra-high rutting resistance but insufficient resistance to cracking. To address this, softer hybrid binders with various penetrations were prepared to improve cracking resistance. Unexpectedly, the use of softer binders did not significantly impact the rutting or cracking resistance of the mixtures, contradicting conventional expectations. To investigate this weak correlation between hybrid binder properties and mixture performance, the rheological properties of both binders and mastics were characterized. The results revealed that the addition of fillers transformed the hybrid binder into a leather-state material, characterized by high modulus and low phase angle. The performance of mixtures was highly related to the semi-crystalline and melting behavior of the PA resin. The state of PA was observed in mastic but not in the binder. The performance of the mixtures was strongly correlated with the properties of the mastic rather than the binder.]]></description>
      <pubDate>Wed, 14 May 2025 08:54:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2537713</guid>
    </item>
    <item>
      <title>Cumulative effects of cracking in monoblock multipurpose precast concrete sleepers on railway tracks</title>
      <link>https://trid.trb.org/View/2481765</link>
      <description><![CDATA[This work addresses the phenomenon of cracking in multipurpose precast monoblock concrete sleepers by examining the entire process from fabrication to final installation on railway tracks. This includes stages such as manufacturing, stockpiling, track installation for rail neutralization, and eventually fastening the rails to the sleepers. A nonlinear numerical model, which is experimentally validated, is used to analyze this effect. Also, thermal and mechanical actions are considered at each stage of the process. Accordingly, different types of polymeric dowels and concrete aggregates—siliceous and carbonate—are evaluated to assess their impact on cracking. The results indicate that the thermal expansion capacity and elastic stiffness of the dowels, as well as the outdoor temperatures during fabrication, stockpiling, and installation, play critical roles in the cracking process. Sleepers made with carbonate aggregate, stiff-expansive dowels, fabricated in cold environments, and installed in hot conditions are particularly prone to severe cracking. Consequently, these conditions should be avoided to minimize cracking in multipurpose sleepers.]]></description>
      <pubDate>Tue, 18 Feb 2025 10:56:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/2481765</guid>
    </item>
    <item>
      <title>High-selective platinum and palladium capture using polyamide 6: A potent material for platinum group metals’ recovery from spent car catalytic converter</title>
      <link>https://trid.trb.org/View/2445825</link>
      <description><![CDATA[Platinum (Pt) and palladium (Pd) are commonly integrated into automotive catalytic converters to convert harmful emissions into relatively safer substances. Their scarcity has resulted in the rapid development of an industry focused on their recovery. Polyamide 6 (PA6), a microplastic pollutant, is a common industrial material. Proper recycling of PA6 can mitigate the environmental impact caused by its microplastic pollution. This work revealed the capability of PA6 in recovering Pt and Pd from solution. Experimental data demonstrated that PA6 recovered about 90% of Pt and 70% of Pd. Importantly, PA6, without any functionalization or modification, adsorbed Pt and Pd without adsorbing present competing metals, exhibiting notably greater recovery selectivity towards Pt and Pd than materials discussed in other works. Furthermore, approximately 81% of Pt and 83% of Pd could be desorbed from PA6 as noted by the desorption studies. After obtaining fitted results using empirical equations and surface group identification, chelation and electrostatic interaction were discerned to be the key pathways for Pt and Pd recovery. This study represents a novel investigation into PA6's adsorption selectivity for Pt and Pd, through which experimental results confirm PA6's potential as a practical, environmentally-friendly alternative for Pt and Pd recovery, distinguishing it from its conventional counterparts.]]></description>
      <pubDate>Mon, 18 Nov 2024 14:21:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2445825</guid>
    </item>
    <item>
      <title>Analytical Study of Durability and Contact Characteristics of Metal-Polymer Composite Sliding Bearings for Means of Transport</title>
      <link>https://trid.trb.org/View/2417270</link>
      <description><![CDATA[The field of application of metal-polymer bearings is vast: transport of various types, processing industry equipment, medical equipment, various types of maintenance equipment, etc. With the use of the developed generalized author's analytical method of metal-polymer plain bearings on the basis of which it is laid the author's research methodology of materials wear kinetics at sliding friction (dry, lubricated), calculation of their durability is carried out. Contact parameters are also determined. Metal-polymer bearings with a bushing made of PA6, PA66 polyamide and PA6 based composites filled with glass (PA6 + 30GF) and carbon (PA6 + 30CF) dispersed fibres, molybdenum disulphide (PA6 + MoS2) and oil filled cast polyamide (PA6 + oil) are considered. These polyamides (unfilled and filled), as self-lubricating materials, are widely used in this type of dry friction sliding bearings. The predictive estimation of durability of investigated bearings depending on loading, polymer materials Young's modulus, their wear resistance and sliding friction coefficient is executed. Regularities of change from the specified factors of bearing's durability and the maximum contact pressures are established. Experimental indicators, diagrams, and wear resistance characteristics of the specified polymeric materials are presented. The results of researches of sliding friction coefficient and modulus of elasticity for carbon steel (0.45%C) – polyamides tribocouples are presented.]]></description>
      <pubDate>Tue, 20 Aug 2024 16:17:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2417270</guid>
    </item>
    <item>
      <title>Preparation and performance analysis of polyamide-based rapid repair material for asphalt pavement shallow groove</title>
      <link>https://trid.trb.org/View/2345809</link>
      <description><![CDATA[In order to effectively remedy shallow grooves on asphalt pavements, this study presents an innovative solution, termed Polyamide-based Asphalt Pavement Shallow Groove Rapid Repair Material (PA-SGRRM). This material employs polyamide 6 (PA6) as the matrix resin, in conjunction with polypropylene (PP), ethylene-vinyl acetate copolymer (EVA), and maleic anhydride-grafted polyethylene-octene copolymer (POE-g-MAH). It is manufactured through an extrusion granulation process. At the outset, a molecular dynamics approach was employed to assess the compatibility of the primary constituents and the adhesion between the matrix resin and asphalt, confirming the rationale behind the material selection. Subsequently, the orthogonal experimental design method was utilized to investigate the influence of design parameters (POE-g-MAH content, PP content, and EVA content) on the flexural strength, tensile strength, low-temperature toughness, and melt flow rate of PA-SGRRM. Following this, the authors prepared samples with the optimal proportions of EVA and POE-g-MAH and conducted a separate analysis to evaluate the impact of PP on the saturated moisture content of PA-SGRRM. Finally, the authors employed Scanning electron microscopy (SEM) to observe the microstructures of the low-temperature fracture surface and ambient temperature tensile fracture surface of the PA-SGRRM and employed Fourier transform infrared spectroscopy (FTIR) to deduce the primary chemical reactions occurring within the PA-SGRRM. The results demonstrated that POE-g-MAH played a crucial role in enhancing the compatibility of the simulated hybrid system consisting of PP and PA6. Additionally, it was observed that adhesion between PA6 and asphalt existed, with a gradual decrease as temperature rose. The content of POE-g-MAH and PP were the two primary parameters influencing the performance of PA-SGRRM. POE-g-MAH exerted a significant adverse impact on the flexural strength, tensile strength, and melt flow rate of PA-SGRRM, while substantially improving its low-temperature toughness. The PP positively reduced the water absorption characteristics of PA-SGRRM. Based on the experimental results, the optimal combination of design parameters for PA-SGRRM is recommended.]]></description>
      <pubDate>Fri, 19 Apr 2024 09:38:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2345809</guid>
    </item>
    <item>
      <title>Effect of fibre type and utilisation rate on dimensional stability and frost resistance of pavement mortar mixture</title>
      <link>https://trid.trb.org/View/2310736</link>
      <description><![CDATA[In this study the effect of fiber type and utilization ratio on the dimensional stability and durability properties of pavement mortar mixtures was investigated. Three different fibers that are 12 mm long polypropylene, polyamide, and basalt fiber were used at a ratio of 0.25%, 0.50%, 0.75%, and 1% of their total volume. Drying-shrinkage, alkali-silica reaction (ASR), sulfate, freeze-thaw, and abrasion resistance of the mixtures were investigated. The findings to emerge from this study are as in the following: first, fiber addition prevented crack growth due to drying shrinkage of cementitious systems. Second, mixtures containing fiber showed higher performance in ASR and freeze-thaw whereas they underperformed in terms of sulfate resistance. These results could be attributed to a dual mechanism; on the one hand, the use of fiber is considered to create an additional void for the products that have the potential to form expansion to escape. On the other hand, the permeability of the mixtures increases as the void volume does due to the use of fiber. The former mechanism is considered to be predominant in ASR and freeze-thaw states. Specifically, mixtures containing basalt fiber with the highest modulus of elasticity outperformed in all properties.]]></description>
      <pubDate>Mon, 01 Jan 2024 11:20:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2310736</guid>
    </item>
    <item>
      <title>An empirical model to predict elongation of polyamide mooring lines</title>
      <link>https://trid.trb.org/View/2291637</link>
      <description><![CDATA[Polyamide mooring lines are being proposed for station-keeping of floating wind turbines in shallow water. However, their mechanical behaviour is quite different to that of the polyester fibre ropes used for deep water offshore oil & gas platform moorings. This paper presents an empirical model which can predict the specific strain response of a polyamide 6 mooring line under stochastic loading. Particular attention is given to the non-linear load-strain behaviour, hysteresis, and the influence of loading history. The identification of the model, using 12 stochastic tests performed on wet 3-strand polyamide sub-rope samples, is described. This model reproduces the specific features of the response of fully wetted PA ropes well, with reasonable accuracy and, for the extreme (maximum and minimum) values it provides a much better prediction than the linear “dynamic stiffness” model. This new model can be integrated in the time domain processing of a suitable mooring analysis software.]]></description>
      <pubDate>Fri, 17 Nov 2023 09:01:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2291637</guid>
    </item>
    <item>
      <title>Investigation and Analysis of the Influences of Glass Fiber Content and Orientation on the Dimension Change of Reinforced Polyamide Parts due to Moisture Absorption</title>
      <link>https://trid.trb.org/View/1802604</link>
      <description><![CDATA[The investigations in this work were focused on the determination and analysis of the factors such as contents and orientations of glass fibre, which influence the dimension change of reinforced polyamide parts significantly. The influence of various environmental conditions on dimensional changes of reinforced polyamide parts was also investigated and a correlation between the dimension change, glass fiber content and orientation under various conditions has been established.         On the basis of process parameters in the injection molding of the tested standard specimens and technical parts, the glass fibre orientations in the part were simulated with help of the software tool MoldFlow. In correlation with the determined expansion coefficients of standard specimens, the expansion of further standard specimens and of technical parts was calculated by the help of Finite Element Analysis. The calculated results for the polyamide parts were compared with the measured values.]]></description>
      <pubDate>Tue, 23 May 2023 09:27:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/1802604</guid>
    </item>
    <item>
      <title>Investigation and Description of the Weight and Dimension Change of Injection Molded Polyamide Parts by Moisture Absorption</title>
      <link>https://trid.trb.org/View/1799213</link>
      <description><![CDATA[In the scope of this work, the weight and dimensional changes of norm test pieces and technical parts (e.g. cages) of reinforced and unreinforced polyamides due to moisture absorption have been investigated. The diffusion coefficients of the tested polyamides for various conditioning environments were determined on the basis of the test results. The weight change due to moisture absorption as function of conditioning time can be represented within a limited tolerance from the measured results by using the Fick's Diffusion Law and an appropriate geometric factor. Furthermore, the dimensional change in relation to weight increase of tested parts were determined and presented here. Further, the influences of fiber content and orientation on the dimension change of various reinforced test parts were investigated.]]></description>
      <pubDate>Wed, 29 Mar 2023 16:46:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/1799213</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>Polyamide 6 Reinforced with Carbon Nanotubes for Automotives Parts</title>
      <link>https://trid.trb.org/View/1816611</link>
      <description><![CDATA[A polyamide 6 reinforced with multi-walled carbon nanotubes (MWCNT) was composed using the melt mixing method. The mechanical and electrical properties were assessed and the optimum concentration was obtained in terms of several properties perspectives.]]></description>
      <pubDate>Mon, 28 Nov 2022 09:16:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/1816611</guid>
    </item>
    <item>
      <title>Short and long term creep behaviour of polyamide ropes for mooring applications</title>
      <link>https://trid.trb.org/View/1994491</link>
      <description><![CDATA[Polyamide 6 fibres are of interest for mooring lines of floating wind turbines and these are continuously loaded throughout their service life. Such applications require the long term response of polyamide 6 ropes in water to be characterized. This paper presents results describing the long term creep behaviour of polyamide 6 sub-ropes with tests that lasted 2 years. A specially designed experimental set-up for long term creep test in water is presented first. Then, a kinetic study comparing creep and recovery is performed using a logarithmic identification of the strain rate. The need for performing long term creep tests is evaluated by comparing the long term creep results to those from short term creep tests lasting 3 h. The results show that a 3 h long creep test provides a reasonable prediction of long term creep strain using a single logarithmic linear law. Finally, a latch-based Weibull model is compared to a single linear logarithmic law to describe and predict creep and recovery response. It is shown that the Weibull model allows a better description of the recovery behaviour of polyamide 6 but is less well adapted for the description of creep.]]></description>
      <pubDate>Thu, 21 Jul 2022 11:42:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/1994491</guid>
    </item>
    <item>
      <title>Improvement on the high-temperature performance and fuel resistance of SBS modified asphalt by hybridizing with polyamide resin</title>
      <link>https://trid.trb.org/View/1885201</link>
      <description><![CDATA[Binders with good high-temperature performance and fuel resistance are urgently needed in paving construction to deal with the challenge of heavy traffic load. Hybrid binders of styrene-butadiene-styrene tri-block copolymer (SBS) modified asphalt and polyamide (PA) resin were prepared with various ratio. The influence of PA content on the performance of binders and mixtures was evaluated by rheological methods, dynamic stability, residual Marshall Stability ratio after immersing in kerosene, bending test and the indirect tensile (IDT) strength ratio after freeze–thaw cycle. The results showed that PA could improve the high-temperature performance and fuel resistance. The hybrid binder with 30% PA content has excellent high-temperature performance, fuel resistance and good workability at the same time.]]></description>
      <pubDate>Thu, 11 Nov 2021 15:21:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/1885201</guid>
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