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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>
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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>Analysis of Cast Aluminium-Zinc Alloy Surface Fatigue Crack Formation Growth Characteristics</title>
      <link>https://trid.trb.org/View/2348366</link>
      <description><![CDATA[Utilizing a scanning electron microscope, research was conducted on the formation of fatigue microcracks in a cast AF620 alloy. The results of fatigue microcrack propagation under escalating levels of stress indicate that the interdendritic or grain boundaries of Al grains are crucial for microcrack propagation. In Al78Zn25 regions, fatigue fractures frequently form within the grains, but if the stress concentration is high enough, they can also form at the base of the crevice on the grain boundaries. The fatigue fracture propagates in a wave-like pattern under a microscope. It was proposed that the length of the crack and the rate of formation of fatigue microcracks could be correlated to ascertain the opening displacement at the tip of the crack.]]></description>
      <pubDate>Mon, 15 Apr 2024 08:37:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2348366</guid>
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    <item>
      <title>Effect of Lubricating Base Oil on the Morphology and Nanostructure of Diesel Particles</title>
      <link>https://trid.trb.org/View/2018355</link>
      <description><![CDATA[In this paper, the influences of lubricating base oils on diesel particles morphology and nanostructure were investigated. Four different lubricating base oils were blended in diesel at a mass ratio of 0.5% and 1.0% for combustion. Exhaust particle samples generated by a four-cylinder, four-stroke direct injection engine when employing neat diesel and four base oil dosed mixtures as the fuel were collected and compared. Primary particle diameter distributions and particle nanostructure were compared and analyzed by a High-Resolution Transmission Electron Microscope (HRTEM). Conclusions drawn from the experiments indicated that the primary particles diameter ranges from 5 nm to 70 nm and the distribution conformed to typical Gaussian distribution. Base oil II, III, IV increased the primary particles diameter, while particles from base oil I exhibited smaller size than that from neat diesel. It is mainly because that the higher content of P and S in the base oil I led to the formation of more nuclear particle emissions. Besides, particles from base oil blended fuels showed same chain-like and branch-like cluster and core-shell nanostructure with particles from neat diesel. The analysis results of particle nanostructure showed that although the chemical compositions of these four base oils were different, four different base oils led to shorter fringes with higher tortuosity and separation distance, which means that the combustion of base oils led to particles with a disordered nanostructure.]]></description>
      <pubDate>Fri, 23 Sep 2022 17:03:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2018355</guid>
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    <item>
      <title>Morphological Characterization of ABS and PC-ABS Surfaces for Automotive Industry</title>
      <link>https://trid.trb.org/View/2004528</link>
      <description><![CDATA[In the automotive industry, the measurement, control and reproducibility of certain morphological characteristics of surfaces are important to characterize, qualify, certify and optimize different physical properties, such as the degree of wear, the degree of adhesion by adhesives, glues or paints and optical properties. In this regard, this work is intended demonstrate how it is possible to characterize different surfaces in ABS (Acrylonitrile Butadiene Styrene) and PC-ABS (PolyCarbonate/Acrylonitrile Butadiene Styrene) through a set of morphological parameters defined according to the ISO 25178 standard. These surfaces have been subjected to different etching treatments performed with different chemicals, which can radically modify the morphology of the surface, making it more or less suitable according to the industrial purposes sought. Furthermore, in this work an analytical relationship between the hybrid parameters Sdq and Sdr defined in the ISO-25718 standard is also proposed, valid for many surfaces of general use. This study is based on the use of a confocal optical microscope and a SEM (Scanning Electron Microscope), which allow surface morphology to be studied at the micro/nano scale and the measurements are analyzed with special imaging and three-dimensional scanning software that allows the precise measurement of morphological parameters of the standard ISO-25178.]]></description>
      <pubDate>Thu, 18 Aug 2022 15:06:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2004528</guid>
    </item>
    <item>
      <title>DPF Loading Analysis by a New Experimental Modus Operandi</title>
      <link>https://trid.trb.org/View/1819279</link>
      <description><![CDATA[The loading of a DPF entails the need of trap regeneration by particulate combustion, whose efficiency and frequency are somehow affected by the way soot is deposited along the channels. The aim of this work is therefore the development of a new experimental methodology able to provide fundamental information about the soot loading process inside the DPF, in order to take advantage of this insight for DPF design and optimization purposes. Small lab-scale 300 cpsi DPF samples were loaded downstream of the DOC in an ad hoc designed reactor capable of hosting 5 samples, by diverting part of the entire flow produced by an automotive diesel engine at 2500 rpm × 8 BMEP, selected as representative of the most critical operating conditions for soot production during the New European Driving Cycle (NEDC).         Soot layer thickness was then estimated by means of FESEM observations after sample sectioning at progressive locations, obtained through a procedure specifically defined in order to avoid affecting the soot distribution inside the filter and to enable estimation of the actual soot thickness along the channel length.]]></description>
      <pubDate>Thu, 21 Jul 2022 13:39:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/1819279</guid>
    </item>
    <item>
      <title>Study of the Mechanical Behavior of an Inconel 718 Aged Superalloy Submitted to Hot Tensile Tests</title>
      <link>https://trid.trb.org/View/1824403</link>
      <description><![CDATA[This study aims to determine some mechanical properties of an Inconel 718 aged superalloy obtained through hot tensile tests.  These properties as conventional 0.2% yield strength (σv), ultimate strength (σUTS), and specific elongation assessment (εu) are important parameters in the study of the mechanical material behavior.  The superalloy was subjected to hot tensile tests at 650 to 700°C and a strain rate of 0.5 mm/min according to ASTM E-8.  It is used a scanning electron microscope (SEM) to obtain images of the fracture surface of the specimens.  The images of the fracture surface are analyzed in order to relate the temperature of the test with the type of mechanism of fracture.]]></description>
      <pubDate>Fri, 17 Jun 2022 09:20:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/1824403</guid>
    </item>
    <item>
      <title>SEM Imaging at Multiple Voltages of Friction Films</title>
      <link>https://trid.trb.org/View/1828394</link>
      <description><![CDATA[This work proposes to acquire images with multiple electron beam energies in the scanning electron microscope to get more information on the lateral distribution of the carbonaceous layer on the surface of friction films formed in brake couples, by combining the backscattered electron images with the behavior of the intensities of the major characteristic X-ray lines as a function of electron beam energy.]]></description>
      <pubDate>Tue, 24 May 2022 10:09:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1828394</guid>
    </item>
    <item>
      <title>Porosity Characterization of Cast Al Alloys with X-Ray Computed Tomography and Scanning Electron Microscope</title>
      <link>https://trid.trb.org/View/1847580</link>
      <description><![CDATA[Cast Al-Si alloys are widely used in automotive industry to produce structural components, such as engine block and cylinder head, because of the increasing demands in reducing mass for improved fuel efficiency. The fatigue performance of the castings is critical in their application. Porosity is highly detrimental to the fatigue behavior of cast Al-Si alloys. Therefore, accurate measurement of pore sizes is important in order to develop the correlations between porosity and fatigue strength. However, quantification of porosity is challenging and shows large variation depending on the measurement methods, particularly for micro-shrinkage porosity due to the torturous and complex morphology. The conventional metallographic image analysis method in the 2D polished surface often underestimates the actual pore size particularly when the porosity morphology is complex. In this study, two experimental techniques including X-ray Computed Tomography (X-ray CT) and scanning electron microscope (SEM) are adopted to characterize the size and morphology of porosity for cast Al-Si alloys. Samples were taken from high pressure die casting (HPDC) blocks made of A380 alloy. Pore size distribution in the sample was extracted from X-ray CT scan data and analyzed using Generalized Extreme Value Distribution (GEVD) function. The Equivalent Circular Diameter (ECD) 3-sigma values were obtained to represent the pore size at each location in the sample, which was validated using the maximum ECD pore size observed on the fracture surface with SEM. This study provides an effective and reliable approach to quantify the porosity which can be applied to predict fatigue properties based on the pore size.]]></description>
      <pubDate>Tue, 26 Oct 2021 14:30:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/1847580</guid>
    </item>
    <item>
      <title>Tribological enhancement of piston skirt conjunction using graphene-based coatings</title>
      <link>https://trid.trb.org/View/1837888</link>
      <description><![CDATA[Piston skirt to cylinder liner conjunctions are amongst the major contributors to frictional power losses of Internal Combustion Engines (ICEs). Efforts have been made to mitigate the frictional losses of these conjunctions by incorporating different technologies such as texturing and application of novel coatings. Any potential technology needs to provide adequate wear resistance as well as frictional reduction in order to be practically applicable. In this paper, the piston skirt of a gasoline engine is deposited by three different variants of Graphene Oxide (GO) coatings deposited using an Electro-Phoretic Deposition (EPD) method. Their tribological performance is benchmarked against uncoated steel and graphite coated aluminium skirts. These coatings are experimentally characterised in terms of asperity level friction, topography and wear resistance. The conjunction and system level performance of these coatings considering both boundary and viscous friction and system dynamics are then evaluated using a multi-physics tribo-dynamic model. Results show that by incorporating an appropriate GO coating, the frictional power loss of the piston skirt to cylinder liner conjunction can be improved by up to 14% whilst maintaining the wear resistance of the coating at the level of an uncoated steel surface.]]></description>
      <pubDate>Thu, 22 Apr 2021 17:46:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/1837888</guid>
    </item>
    <item>
      <title>Comparing Micro- and Macro-Level Rheological Properties of Polymeric and Reclaimed Asphalt Pavement-Modified Asphalt Binders</title>
      <link>https://trid.trb.org/View/1759258</link>
      <description><![CDATA[Multi-scale evaluation of the rheological and mechanical properties of asphalt binder has substantial importance in understanding the binder’s micro- and macro-scale properties. This study compares the macro- and micro-scale mechanistic properties of asphalt binders. Test samples used in this study include performance grade binders (PG 64-22) from two different sources along with their modified counterparts. The modifiers include polyphosphoric acid (PPA), styrene-butadiene-styrene (SBS), a combination of SBS and PPA, and reclaimed asphalt pavement. To achieve the goal of this study, atomic force microscope technology was utilized to estimate the asphalt binder’s micro-mechanical properties (e.g., Derjaguin, Muller, Toropov modulus and deformation). On the other hand, data on the macro-scale properties—such as rutting factor (G*/sind), consistency and penetration—of the selected binders were analyzed and compared with the aforementioned micro-level properties. The comparative analyses indicated that the micro-mechanical properties of asphalt binders followed a linear trend with the macro-scale properties. The findings of this study are expected to help researchers and pavement professionals in modeling asphalt materials when multi-scale effects are deemed to be necessary.]]></description>
      <pubDate>Thu, 04 Feb 2021 10:57:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/1759258</guid>
    </item>
    <item>
      <title>Fatigue life prediction of heavy vehicle suspension system under varying load conditions</title>
      <link>https://trid.trb.org/View/1754711</link>
      <description><![CDATA[Leaf spring experiences frequent cyclic loading during working conditions. When design stage itself it is very essential to assess the fatigue life of the suspension system. It is important to consider and evaluate the key aspects of fatigue failure and life by using Finite Element Analysis (FEA) techniques to overcome these failures. This paper serves to stimulate the premature failure of the existing and proposed bracket model with generalized force elements under dynamic load conditions. Scanning Electron Microscope (SEM) was used to identify the bracket failure prone areas which indicate that the cyclic load in the suspension system is caused by rural area road-induced vibrations and bumps. This contributes to the increase of the fatigue fracture, which ends up with a bracket failure. The results indicated that the fatigue life of existing bracket is low for rough road conditions; the modified bracket has been optimized for the safe load conditions of the heavy vehicle suspension system]]></description>
      <pubDate>Mon, 21 Dec 2020 10:02:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/1754711</guid>
    </item>
    <item>
      <title>Exploration of Dry Sliding Wear Behaviour of Sisal Fiber Reinforced Cashew Nut Shell Liquid and Epoxy Polymer Matrix Composite as an Alternative Friction Material in Automobiles</title>
      <link>https://trid.trb.org/View/1660533</link>
      <description><![CDATA[The brake pad is one of the foremost imperative parts of the vehicle. Due to the environmental requirement, natural materials were the alternate source for products manufacturing. The product composite made by using hot press techniques with mixing ingredients such as natural fiber (treated sisal), cashew nut filler, graphite and alumina with resin (cashew nut shell liquid - CNSL and epoxy). Two formulas and four samples of each set were composed by varying the resin type of CNSL and epoxy and prepared the test samples with attaining better hardness. The main intern of this proposed effort is to appraise the wear in dry sliding and performance of friction of the prepared composites. The composites are taken for tribo test by varying the load of 10,20,30,40 N and sliding distance of 1000, 2000 m respectively. Experiments were performed at stated process parametric conditions to record the responses. The result shows that the CNSL resin composites specific wear resistance and frictional coefficients are found better than epoxy resin composites. The addition of filler element cashew nut shell particular shows a better wear resistant and friction coefficient. On the other hand, low wear resistance and low friction coefficient were appraised at a high load of 40 N and sliding distance of 2000 m tribo parametric conditions. Further scanning electron microscopic analysis was carried out to observe wear mechanics with the formation of very fine debris on the worn surface and counter face of the composite.       ]]></description>
      <pubDate>Fri, 28 Feb 2020 10:12:54 GMT</pubDate>
      <guid>https://trid.trb.org/View/1660533</guid>
    </item>
    <item>
      <title>Experimental Investigation on Mechanical Properties and Vibration Damping Frequency Factor of Kenaf Fiber Reinforced Epoxy Composite</title>
      <link>https://trid.trb.org/View/1660527</link>
      <description><![CDATA[Kenaf Fiber regarded as industrial crop for different applications. It is one of the most important plants cultivated for natural fibers globally. Natural fibers such as kenaf fibers are getting attention of researchers and industries to utilize it in different composites due to its biodegradable nature. In this present investigation mechanical properties, vibration damping frequency factor and thermogravimetric analysis of kenaf fiber reinforced epoxy composite (KFREC) have been evaluated and reported. The tests were conducted with different weight categories of kenaf fiber such as 20%, 25%, 30% and 35%. The effects of fiber content on tensile, flexural, impact strengths, hardness and thermal decomposition properties of the composite were determined. The failure mechanism and damage features of the KFREC were categorized using Scanning Electron Microscope (SEM). The results indicate that the increase in the fiber content decreases the damping vibration factor (?) correspondingly. The lowest value of the damping vibration factor was recorded as 0.033 for 35% weight content of Kenaf fiber in the composite. The maximum value of hardness, tensile, flexural, and impact strengths were noted as 447 BHN, 45.62 MPa, 124 kN and 13.2 J respectively and the effective thermal decomposition range was 378.64 - 442.18 °C for 35% of kenaf weight content KFREC. From the results it is identified that the kenaf fiber at 35% weight content reinforced with epoxy resin will be suitable for structural application in automobiles such as bumper beams, door panels and front modules. In addition to that the light weight nature of the kenaf fiber will help in achieving fuel economy in automobiles.       ]]></description>
      <pubDate>Fri, 28 Feb 2020 10:12:54 GMT</pubDate>
      <guid>https://trid.trb.org/View/1660527</guid>
    </item>
    <item>
      <title>Etude en microanalyse sur des échantillons prélevés sur les remblais de l'A304</title>
      <link>https://trid.trb.org/View/1673711</link>
      <description><![CDATA[The micro-analysis, supplemented by X-ray diffraction (XRD) results, is conducted for compare the different materials extracted from the original embankment through observation of the microstructure and analysis of the mineral phases present. These comparisons serve to demonstrate similarities or differences in structures or composition, and highlight any evolutions, to demonstrate the presence or the absence of a trace of treatment, and to attempt to provide information on a mechanical behavior. The use of different methods of observation and analysis of the six (6) materials from A304 embankments have shown that lime treatment indices out of five (5) of these six materials. This study shows above all that it is necessary to have recourse to both chemical / mineralogical analyzes and imaging (electronic or optical) validate the presence of a treatment.]]></description>
      <pubDate>Wed, 18 Dec 2019 12:14:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/1673711</guid>
    </item>
    <item>
      <title>Investigation of Laboratory and Field Aging of Bituminous Concrete with and without Anti-aging Additives using FESEM and FTIR</title>
      <link>https://trid.trb.org/View/1632330</link>
      <description><![CDATA[It is a well-known fact that aging of bituminous binder induces physical, chemical and morphological transformations. During the current investigations, an attempt was made to monitor the aging phenomenon of VG 30 grade bituminous binder through penetration index, sulfoxide index, carbonyl index, FTIR and FESEM studies. Bituminous concrete samples, prepared in line with field specifications, were artificially aged with oven (as per AASHTO R30). Further, the extracted samples were investigated for understanding the transformations taking place with aging. Attempts were also being made to investigate the influence of warm mix additive i.e., Sasobit and hydrated lime on aging process. Bitumen extracted from field aged samples was also tested and the performance was compared with that of the lab aged samples for assessing the level of match between the laboratory and field aging processes. It was established through the tests and indices developed during the study that the addition of Sasobit (warm mix additive) and hydrated lime has improved the resistance towards aging of VG 30 bituminous binders.]]></description>
      <pubDate>Wed, 21 Aug 2019 09:35:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1632330</guid>
    </item>
    <item>
      <title>Atomic force microscopic measurement of a used cylinder liner for prediction of boundary friction</title>
      <link>https://trid.trb.org/View/1626688</link>
      <description><![CDATA[Accurate simulation performs a crucial role in the design and development of new modern internal combustion engines. In the case of piston rings, simulations are used to effectively predict generated friction and power loss of proposed designs. These are consequences of viscous shear of a thin lubricant film, likewise boundary friction caused by direct interaction of piston rings with the cylinder liner/bore surface. The most commonly used model for determining boundary friction is that of Greenwood and Tripp. The model requires the pressure coefficient of boundary shear strength of asperities from the softer of the contacting surfaces as an input. This parameter needs to be measured. The paper describes the process of measurement using an Atomic Force Microscope (AFM), both for a dry surface and that wetted by the presence of a lubricant layer. For realistic results, the investigated specimen is a used, tested engine cylinder liner where boundary active lubricant additives are bonded to its surface as well as combustion products. This approach is as opposed to the previously reported works using new flat surfaces with base oil or partially formulated lubricants and has not been previously reported in the literature. The results show that for used cylinder liners, the measured boundary shear strength of asperities varies according to location along the stroke. Results are reported for the top dead centre, mid-stroke and bottom dead centre locations. The measurements are subsequently used with two-dimensional Reynolds solution for a top compression ring-liner contact, where it is found that accurate localised predictions of generated friction and power loss can be made instead of the usual average value approach reported in the literature.]]></description>
      <pubDate>Tue, 25 Jun 2019 09:57:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/1626688</guid>
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