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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>Fatigue characteristics of cement-stabilized steel slag base course for asphalt pavement structure considering different paving methods</title>
      <link>https://trid.trb.org/View/2487657</link>
      <description><![CDATA[This study investigates different on-site paving methods for the base course, establishing a model using the computational programme GAMES based on the elastic layered system theory. The impact of the number of paving layers, paving thickness and the bonding condition at interfaces between sub-layers on the fatigue characteristics of the asphalt pavement structure with the cement-stabilized steel slag (CSS) base course is investigated. Furthermore, this study explores the impact of factors such as forming method, curing time and cement content on the fatigue characteristics of the CSS mixtures through laboratory indirect tensile test. The results indicate that the impact of the bonding conditions at paving interfaces between sub-layers due to layered paving on the tensile stress at the bottom of the CSS base course is much greater than that of the asphalt surface course. The tensile stress at the bottom of the CSS base course increases first and then decreases as the paving interface moves from top to bottom, indicating the existence of the most unfavourable paving interface. It is recommended to use vibration compaction method for forming the CSS base course to reduce the paving interface, thereby enhancing the fatigue resistance of the pavement structure.]]></description>
      <pubDate>Mon, 10 Feb 2025 17:11:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2487657</guid>
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    <item>
      <title>Monitoring and explainable prediction technique for density of hot mix asphalt during pavement construction via intelligent compaction technology</title>
      <link>https://trid.trb.org/View/2491587</link>
      <description><![CDATA[During the construction of Hot Mix Asphalt (HMA) pavements, compaction is crucial for ensuring the pavement's ultimate performance. Traditionally, in-place density is monitored using in situ spot tests with non-destructive density gauges (nuclear or non-nuclear) calibrated against core sample measurements. However, these density spot tests are often conducted at different intervals, hindering timely assessment. Intelligent compaction (IC) has emerged to enhance this process, equipping rollers with sensors to improve HMA compaction. This study aims to monitor the density of the asphalt pavement and develop predictive models for HMA density during construction, utilizing intelligent compaction measurement values (ICMVs), lanes, and pass counts. Data were collected from a construction project in Pakistan, including IC data from vibratory rollers and non-nuclear gauge (NND) density measurements. Machine learning methods—specifically support vector regression, random forest, extreme gradient boosting, and light gradient boosting—were applied and enhanced with a chaotic firefly algorithm to develop these predictive models. The robust model was interpreted using Shapley’s adaptive explanations (SHAP) to assess the influence of ICMVs on NND. The results revealed that the model's predictions closely aligned with measured NND values, with light gradient boosting demonstrating superior performance during validation and achieving an R2 value of 0.989 and RMSE less than 1.172. The SHAP analysis demonstrated a significant influence of ICMVs, particularly the compaction control value (CCV) and resonant meter value (RMV) with NND. Furthermore, the machine learning model's results outperform previous studies' findings. These findings suggest that utilizing ICMVs and machine learning predictions may effectively replace traditional NND density tests, providing easier and more accurate access for density determination during asphalt construction.]]></description>
      <pubDate>Wed, 29 Jan 2025 17:00:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2491587</guid>
    </item>
    <item>
      <title>Characterization of HMA Internal Structure Using Image Analysis</title>
      <link>https://trid.trb.org/View/2281903</link>
      <description><![CDATA[In this study, an attempt was made to estimate the internal structure characters of HMA (Hot Mix Asphalt). This was done by studying the aggregate orientation, aggregate distribution and internal parameters: φ and C. Four gradations and two types of compaction: vibratory compactor and superpave gyratory compaction (SGC) were analyzed. The results indicate that aggregates compacted using SGC were found to be a more horizontal and uniform distribution but with a larger space between coarse particles (>2.36mm) and smaller C compared with samples compacted using a vibratory compactor. For coarse gradation, the coarse particles were closer and decreased the content of the 2.36mm aggregate and can help the coarse aggregates be compacted more tightly.]]></description>
      <pubDate>Fri, 12 Apr 2024 09:13:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/2281903</guid>
    </item>
    <item>
      <title>A review of effect of compaction methods on cold recycling asphalt mixtures</title>
      <link>https://trid.trb.org/View/2231517</link>
      <description><![CDATA[The application of recycled asphalt materials in pavement rehabilitation has been created and developed in the past several decades. The consideration of sustainable practices become more widespread in the road construction. As one of the recycling technology, cold recycling has been mentioned more frequently. Several countries proposed their own quality requirements and mix design procedure for cold recycling mixture. The focus of this paper is the effect of compaction methods on cold recycling mixtures (CRM). Variety of topics including laboratory compaction methods, mechanical performance, microsturcture, relation to field compaction and environmental, economic benefit of CRM are reviewed to better follow up the development of the cold recycling technology. The result indicates that the number of air voids in gyratory and vibratory specimens is more than other compaction, the average air void size is smaller. In terms of environmental and economic benefit, the VVTM was found to exist higher evaluation among these compaction methods. However, the internal structure and mechanical properties of laboratory CRM cannot fully replicate those of field cores. In further study, optimizing compaction process including compaction and double second compaction needs to be considered.]]></description>
      <pubDate>Wed, 20 Sep 2023 09:08:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2231517</guid>
    </item>
    <item>
      <title>Modeling of asphalt mixture-screed interaction: A nonlinear dynamic vibration model for improving paving density</title>
      <link>https://trid.trb.org/View/1888533</link>
      <description><![CDATA[Paving compaction has an important influence on the significant improvement of the asphalt mixture density during pavement construction, and the paving density is mainly affected by the paver response and material behavior. To improve the density of asphalt pavement, this paper proposes a nonlinear dynamic vibration system of the interaction between asphalt mixture and screed plate. Based on the harmonic balance principle, a multi-degree of freedom nonlinear system of the screed plate-asphalt mixture interaction was established. By considering material characteristics and energy absorption efficiency during paving compaction, a paving density tendency-vibration frequency theoretical model was applied to analyze the influence law of dynamic response of the asphalt-screed interaction on the material density. The analysis results indicated that 1) both the characteristics of the asphalt mixture and the vibration frequency of the screed affected the material density during the paving process; 2) the optimal vibration frequency was higher than the natural frequency, and further compaction with a lower vibration frequency can effectively improve the energy absorption efficiency; 3) for the screed in movement, only when the vibration frequency enters the resonance region of the high-density mixture can a better compaction effect be obtained. Finally, the nonlinear dynamic model was experimentally verified. The research results are beneficial for improving the paving density and the quality of asphalt pavement, providing a basis for the effective compaction of asphalt pavement.]]></description>
      <pubDate>Wed, 17 Nov 2021 14:29:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/1888533</guid>
    </item>
    <item>
      <title>Meso-Scale Kinematic Responses of Asphalt Mixture in Both Field and Laboratory Compaction</title>
      <link>https://trid.trb.org/View/1850049</link>
      <description><![CDATA[Compaction is one of the most critical steps in asphalt pavement construction. Traditional compaction relies heavily on engineering experience and post-construction quality control and can lead to under/over compaction problems. The emerging intelligent compaction technology has improved compaction quality but is still not successful in obtaining mixture properties of a single pavement layer. Besides, very few studies have discussed the internal material responses during field and laboratory compaction to explain the meso-scale (i.e., particle scale) compaction mechanism. Knowledge in those areas may greatly promote the development of smart compaction. Therefore, this study aims to investigate the kinematic behavior of the asphalt mixture particles (translation and rotation) under six types of field and laboratory compaction methods and establish the relationship between the field and the laboratory compaction by using a real-time particle motion sensor, SmartRock. It was found that particle movement pattern was mainly affected by the compaction mode. At the meso-scale where particle behavior is the focus, the kneading effects of a pneumatic-tire roller can be simulated by laboratory gyratory and rolling wheel compaction, and the vibrating effects of a vibratory roller can be simulated by Marshall compaction. However, none of those laboratory compaction methods can completely simulate the field compaction. Under vibratory rolling, particle acceleration decreased fast in the breakdown rolling stage. Under pneumatic-tire rolling, particle angular position change was related to aggregate skeleton, and particle relative rotation showed a decreasing trend that was consistent with the laboratory gyratory compaction results. Those kinematic responses can potentially be used to monitor density change in field compaction.]]></description>
      <pubDate>Tue, 11 May 2021 12:23:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/1850049</guid>
    </item>
    <item>
      <title>Innovative Compaction Rollers for Improving the Performance and Life of HMA Pavements</title>
      <link>https://trid.trb.org/View/1743196</link>
      <description><![CDATA[Good compaction is the key factor to construct durable, long life pavements. Higher and more uniform density of hot mix asphalt (HMA) mixes means increasing pavement life. That’s a reason why it’s important to use right compaction equipment with appropriate compaction modes such as static, vibration, oscillation, kneading, impact, etc., to obtain good performance of HMA pavement. The innovative compaction modes implemented in two types of new roller are introduced in this paper. They are very effective to achieve good performance of the HMA pavement such as durability, low noise and low rolling resistance. First one is the vibratory pneumatic tire (VPT) roller weighing 9t that was developed in Japan. The effectiveness has come to light through comparison test with a conventional heavy static pneumatic tire (SPT) roller weighing 25t. It was found that that VPT roller achieves the required level of density in HMA mixes by fewer rolling passes and more uniform density distribution throughout the depth of HMA pavement layer than those by SPT roller. Second one is dual drum oscillatory/vibratory roller, in which either oscillation or vibration for both drums can be selected as required. Especially, the optimum amount of the oscillatory amplitude in dual drums is helpful to prevent hair cracking and shoving over the pavement surface while rolling, and make the surface texture uniform to lower the noise that occurs between tires and pavement surface.]]></description>
      <pubDate>Wed, 03 Feb 2021 15:00:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/1743196</guid>
    </item>
    <item>
      <title>Impact of vibration compaction on the paving density and transverse uniformity of hot paving layer</title>
      <link>https://trid.trb.org/View/1685067</link>
      <description><![CDATA[The compaction performance of asphalt pavement depends upon not only the material design but also the construction procedure. This paper intends to quantitatively evaluate the impacts of material properties and paving parameters on the paving compaction quality (i.e., the density and uniformity). A vibration model of screed-paving layer interactions was built to simulate the screed vibration response and the vibration transmission to the paving layer with the vibration frequency and material stiffness. Then, the force transmitting ratio (FTR), contact force, moment transmitting ratio (MTR) and transmitting rotation moment were used to evaluate the compaction of the paving layer. Moreover, a quantized density model was proposed to quantitatively predict the paving compaction performance. In contrast to traditional analyses, the transverse amplitude uniformity of the screed was considered in this work. Finally, the simulation model was validated through a field test. The results show that the paving layer stiffness is positively associated with the initial layer density, which depends on the tamper frequency. For the case study in this paper, the optimum frequency is approximately 163 rad/s, 175 rad/s and 190 rad/s when the tamper frequency is 19 rad/s, 57 rad/s and 95 rad/s, respectively. Larger variation coefficient (CV) and density ratio (DR) indicate that the uniformity of the paving layer density distribution and the pavement roughness are worse. Therefore, it is recommended that the screed vibration frequency and mixture stiffness, which both affect the paving layer density and compaction uniformity, should be considered for future construction procedures.]]></description>
      <pubDate>Tue, 17 Mar 2020 14:27:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/1685067</guid>
    </item>
    <item>
      <title>Nonlinear Dynamics of Asphalt–Screed Interaction during Compaction: Application to Improving Paving Density</title>
      <link>https://trid.trb.org/View/1587790</link>
      <description><![CDATA[Paving compaction is one of the important steps in pavement construction that significantly affects the subsequent roller compaction and the quality of asphalt pavement, which is influenced by several factors related to the paver response and the properties of asphalt mixture. Therefore, it is necessary to relate the dynamic response of screed-asphalt mixture interaction to the change of paving density during asphalt pavement compaction in order to improving paving density throughout the pavement. In this paper, a non-linear dynamical model describing the interaction between the vibratory screed and the asphalt pavement was present to simulate the screed vibration response, the force transmitted to the paving layer (contact force) and the vibration force transmission ratio. Based on the dynamical equations for the coupled system, a mathematical model of trend density to paving density in field was developed with the inputs of asphalt mixture properties, excitation frequency and other mechanical properties of the paver screed. In contrast to traditional analyses, a combination of the response amplitude factor β(ω) representing the magnitude of the screed amplitude and the force transmitting ratio H(ω) representing the ratio of contact force to excitation force was considered in the trend density model. Moreover, the model parameters including the initial density P0 and compaction capacity coefficient P1, which were dependent on the screed specifications and the material properties of the asphalt mixture were calculated using the common and simple lsqcurvefit algorithm, and the simulation model was verified by experiments. Results show that the asphalt mixture with large limit displacement needs further compaction in a relatively low frequency, which can ensure the compaction effort while improving the force transmitting ratio. Further compaction of the asphalt mixture with a small limit displacement comes at the cost of the energy transferred to the paving mat, and the screed has serious vibration. The results also indicate that the excitation frequency higher than the resonance frequency can ensure compaction efficient, while the compaction would be made more efficient and the energy efficiency significantly increases by lowering excitation frequency.]]></description>
      <pubDate>Thu, 18 Apr 2019 11:04:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/1587790</guid>
    </item>
    <item>
      <title>Dynamic characteristics modelling of the tamper–asphalt mixture interaction: application to predict asphalt mat density</title>
      <link>https://trid.trb.org/View/1591364</link>
      <description><![CDATA[Recently, the study of machinery/medium interaction is becoming increasingly important in terramechanics. In order to maximise the performance of existing equipment and obtaining desired compaction density in road construction, reasonable and effective paving operations are essential. However, the operations always depend on empirical approaches. In this paper, a model based on vibration compaction theory was used to describe the deformation property of asphalt mixture, which can lay a foundation for future analysis. And then, a dynamic model of tamper/asphalt mat interaction, based on the principles of resonance, was developed to predict asphalt mat density during paving operation. The model inputs included excitation frequency, tamper stroke, paver forward speed and asphalt mixture properties parameters for different tamper or asphalt mixture. The numerical simulations are provided to demonstrate how the tamper/asphalt mat interaction model can be used to predict asphalt mixture compaction in the field of road construction engineering.]]></description>
      <pubDate>Mon, 25 Mar 2019 20:10:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/1591364</guid>
    </item>
    <item>
      <title>Study of Compactability Models Describing Asphalt Specimen Compaction With Gyratory and With Impact Compactor</title>
      <link>https://trid.trb.org/View/1460538</link>
      <description><![CDATA[The service life of pavement surface courses is highly dependent on the construction process. A large number of parameters have to be controlled and kept at optimum during the laying and compaction process. The compactability of asphalt mix is the most important feature at the time of paving. Proper compaction of the asphalt layer ensures that the pavement can achieve the planned service life, the bearing capacity and the resistance to low and high temperatures. In this study, the compactability determined by the gyratory and impact compactor was investigated. The standardized model as described in the European standard EN 12697-10 for the compaction propagation was evaluated with the data obtained from the tests performed on five different asphalt mixtures. Past research showed that the ‘standardized model’ that is currently used for the impact compactor does not describe the compaction process appropriately. In a published article three new solutions were proposed. With the present study the authors tried to find out if the new proposed models can be used to properly describe compactability of asphalt specimen determined with the gyratory compactor.]]></description>
      <pubDate>Mon, 27 Mar 2017 17:10:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/1460538</guid>
    </item>
    <item>
      <title>Preventing Transverse Bumps and Cracks in New Asphalt Overlays over Crack Sealants (Bumps over Crack Sealants)</title>
      <link>https://trid.trb.org/View/1459005</link>
      <description><![CDATA[Crack sealants are often utilized as a preservation tool in asphalt pavements. These sealants are placed in cracks to prevent water intrusion into the pavement foundation. By reducing water intrusion, the strength of foundation layers is maintained and acceptable pavement performance is extended. However, when a hot mix asphalt overlay is placed on top a pavement containing crack sealants, a bump and additional transverse cracks sometimes occur in the new asphalt overlay. These bumps and sometimes, transverse cracks are initiated during breakdown rolling and become progressively more severe upon further compaction. This paper presents results of a five-year study designed to identify factors that relate to the appearance of these bumps and consequent cracks. Results of the study indicate that vibratory breakdown rolling, pavement gradient, sealant geometry, tack coat application rate and tack coat adhesivity are factors that contribute most to the occurrence of bumps and transverse cracks during asphalt overlay construction over crack sealants. Observations suggest that transverse bumps and consequent cracks occur in proportion to the size of the ‘bow wave’ of asphalt concrete present immediately in front of the breakdown roller. The increase in the ‘bow wave’ size is dependent on asphalt mixture properties, breakdown roller size, speed, vibration characteristics and pavement gradient. Four pavement test sections also indicate that tack coat application rate and adhesive properties also have an effect on reducing the appearance of transverse bumps. The results of the findings are to be presented to the Colorado Department of Transportation (CDOT) Study Panel and to the Materials Advisory Committee (MAC) for review and approval for implementation in the construction of asphalt overlay projects. Since the tack coat application rate is found to have the greatest impact in the formation of bumps in the asphalt overlay, CDOT construction personnel will be advised by respective Region Materials personnel to ensure that the relevant current standard special provisions which already address this issue are enforced strictly in all asphalt overlay construction projects. The MAC will communicate with the Colorado Asphalt Pavement Association (CAPA) to alert the industry about the research findings and the need to follow the required tack coat application procedure more rigorously. CDOT materials, construction and inspection personnel will be asked to coordinate with contractors more closely during asphalt paving operations to ensure that tack coats are applied diligently and accurately in accordance with the specified levels.]]></description>
      <pubDate>Mon, 27 Mar 2017 09:30:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/1459005</guid>
    </item>
    <item>
      <title>Influence of different roller compaction modes on asphalt mix performance</title>
      <link>https://trid.trb.org/View/1370047</link>
      <description><![CDATA[This study aims to investigate the relationship between different roller compaction modes and resulting mechanical performance. In order to accomplish these objectives, a trial asphalt pavement section was observed and monitored both during the paving and compaction processes. Asphalt mix was sampled from the paver to be used later in laboratory and evaluate the differences between compaction in-field and laboratory. Asphalt concrete mixes were prepared and compacted in the laboratory using a steel roller compactor, with varying factors that influence compaction in terms of compaction modes (static, vibratory and a combination of both), as well as effort and temperatures in order to attempt to simulate field compaction conditions. The identification of a harmonised compaction procedure for specimen fabrication able to produce mixtures with stiffness properties resembling field compacted mixtures was also investigated based on the performance-based test results.]]></description>
      <pubDate>Sat, 26 Sep 2015 18:15:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/1370047</guid>
    </item>
    <item>
      <title>Finite element modelling of field compaction of hot mix asphalt. Part II: Applications</title>
      <link>https://trid.trb.org/View/1370044</link>
      <description><![CDATA[A constitutive model is developed and implemented in the finite element system three-dimensional computer-aided pavement analysis for the simulation of hot mix asphalt field compaction. The details of this model are presented in a companion paper (Masad et al., Finite element modelling of field compaction of hot mix asphalt. Part I: Theory, International Journal of Pavement Engineering, Accepted, 2014). This model is based on nonlinear viscoelasticity theory and can accommodate large deformations that occur during the compaction process. The model was used to study the influence of frequency and amplitude of vibratory compaction rollers on the level of compaction. In addition, it was used to analyse the influence of various methods for compacting longitudinal joints on the percent air voids near these joints. The model was used to simulate the compaction of asphalt pavements with different structures and compacted using various equipment and patterns. The finite element results of the level of compaction and percent air voids were in reasonable agreement with the measurements. The model offers the opportunity to simulate and predict the compaction of asphalt mixtures under various rolling patterns and for different pavement structures.]]></description>
      <pubDate>Sat, 26 Sep 2015 18:15:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/1370044</guid>
    </item>
    <item>
      <title>Use of Roller-Compacted Concrete Pavement in Stafford, Virginia</title>
      <link>https://trid.trb.org/View/1356038</link>
      <description><![CDATA[Roller-compacted concrete (RCC) is a relatively stiffer hydraulic cement concrete mixture than regular concrete when fresh. Similar to regular concrete, RCC is a mixture of aggregate, cementitious materials, and water, but it is placed using asphalt pavers and compacted by vibratory rollers, and it hardens into concrete. RCC contains a low amount of water, exhibits no slump, and requires asphalt paving equipment for placement rather than expensive slip-form paving equipment. It does not contain reinforcement, tie-bars, or dowels. RCC can be placed and opened to traffic in a short period of time. All of these factors combined make it a relatively low-cost material for roadways compared to asphalt or conventional concrete pavements. However, RCC may lack the smoothness required for high-speed roadways and can undergo raveling and/or cracking; an asphalt overlay may remedy the smoothness and raveling issues. Although cracks might occur in the RCC and potentially reflect through the asphalt layer, such cracks should stay tight because of the low shrinkage of RCC. A composite pavement with RCC and an asphalt overlay has the potential to be a cost-effective long-lasting pavement system.  The purpose of this study was to document the construction procedures and provide lessons learned for a RCC project recently completed by the Virginia Department of Transportation that covered about 134,000 ft2, equivalent to 2 lane-miles, at the Park & Ride lot in Stafford County, Virginia. About one-third of the RCC was used to rehabilitate the existing Staffordboro Boulevard (Route 684). The mixture used had 15% fly ash to provide improved durability and sustainability. Batches of the RCC mixture fluctuated in moisture content, and delays in placement sometimes occurred that also resulted in wet and dry mixtures. The compaction, surface smoothness, and road profile were affected by the fluctuations in moisture content. RCC cylinders prepared using a vibratory hammer usually exceeded compressive strengths of 1,600 psi and 4,000 psi at 12 hours and 28 days, respectively. Only a few early cracks were observed in the pavement. Opening to traffic at an early age for a section, i.e., within 5 to 6 hours of placement, did not result in any visual damage to the pavement; most sections were opened in less than 48 hours. RCC overlaid with 2 in of asphalt is performing well after two winters and 18 months of traffic for one section and after one winter and 8 months of traffic for the rest.  Based on the observations in this study, for successful construction of RCC, proper compaction and mixing equipment are essential. Achieving the proper level of compaction in the field is key to attaining quality RCC. To avoid early cracks, joints need to be cut deeper than one-fourth depth of the pavement and continuous curing is essential. A continuous paving operation is needed to avoid unplanned and poor-performing cold joints. The Virginia Department of Transportation should consider RCC in future field trials, particularly for applications where fast construction of rigid (concrete) or composite pavement is needed.]]></description>
      <pubDate>Fri, 26 Jun 2015 13:41:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/1356038</guid>
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