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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Mechanical Response of Road Embankments Built on Permafrost located at Inuvik-Tuktoyaktuk Highway</title>
      <link>https://trid.trb.org/View/2665666</link>
      <description><![CDATA[Road construction on permafrost typically involves using thick granular embankments to provide thermal and mechanical protection for the subgrade. A proper structural design is one of the most important factors to minimize the mechanical impact of roads on permafrost. Additionally, seasonal variability plays a vital role in this regard. This study was conducted as a test section along the Inuvik–Tuktoyaktuk Highway (ITH) by embedding several thermal, moisture, pressure cell, and deformation sensors at different depths and distances in a single location. The instrumentation was done in 2019, and the data was recorded continuously until 2024 for analysis. These results were the outcome of six site visits during two different years, with the goal of recording the properties of the embankment and soil under frost, settlement, and heave conditions. During each site visit, a loaded dump truck was driven over the test section under controlled conditions to record data. The truck was driven at three different speeds (5 km/hr, 15 km/hr, and 25 km/hr) on the centerline of the sensors. Additionally, other testing, such as the Light Weight Deflectometer (LWD), was conducted for further analysis. The results of this research show an increase in permafrost degradation and growth of the active layer, based on the mechanical responses from the embankment and soil. The LWD test shows an improved modulus at the surface of the road, in contrast to a decrease in strength in the deeper layers. The changes in climatic/environmental conditions are also impacting the moisture and temperature in the permafrost region due to increasing temperatures.]]></description>
      <pubDate>Thu, 12 Mar 2026 08:52:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2665666</guid>
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    <item>
      <title>Lightweight Aggregates as Frost Insulation in Roads — Design Chart</title>
      <link>https://trid.trb.org/View/2160328</link>
      <description><![CDATA[Frost heave and thawing, resulting in deformations and reduced bearing capacity, cause major maintenance costs of the roads in the Nordic countries. The most common frost protection method in Norway is to increase the layer thickness of crushed rock. In addition has extruded polystyrene (XPS) been used since 1965, but this has gradually been reduced the last 20 years. Light expanded clay aggregate has regularly been used as frost protection for other civil engineering applications such as railways and buildings, and is occasionally also used for pavements. Lately also foam glass aggregate has become an option. To optimize the design, SINTEF has performed a number of numerical analyses and developed design charts that give the required layer thickness of frost insulation. The numerical analyses showed that the frost protection layer using expanded clay or foam glass aggregate should be 4–5 times thicker than a frost protection of extruded polystyrene.]]></description>
      <pubDate>Thu, 18 May 2023 17:08:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/2160328</guid>
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    <item>
      <title>Field Test Comparing Frost Insulation Materials in Road Construction</title>
      <link>https://trid.trb.org/View/2160325</link>
      <description><![CDATA[Three products are presently used in Norway as thermal insulation in roads; lightweight clay aggregate (LWCA), foam glass aggregate and extruded polystyrene boards (XPS). As a evaluation on the present design guidelines for frost insulation and in order to compare the different insulation products, a field test is established in connection with the construction of a new main road (E6) south of Trondheim in Norway. The test site has four different sections. In addition to three sections where each of the three different insulation products are used, one additional section contains ordinary pavement materials produced from crushed rock.]]></description>
      <pubDate>Thu, 18 May 2023 17:08:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/2160325</guid>
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    <item>
      <title>Iron sand as a frost protection layer : thickness design charts</title>
      <link>https://trid.trb.org/View/2145735</link>
      <description><![CDATA[Frost depths and frost heaving calculations were performed to prepare design charts and tables for the iron sand (järnsand) layer thickness design for roads typically used for residential area, parking lots and other low to medium traffic roads, and for ground insulation.  A segregation potential based frost design method was employed to generate the design charts and tables. The segregation potential method allows the prediction of both frost heaving and frost penetration depth of a pavement structure for a prescribed winter temperature profile or freezing index. Thus, the iron sand layer thickness design tables/charts for roads were prepared for different levels of maximum permitted heaving criteria of 50, 80, 100, and 120 mm. Whereas for ground insulation, a design chart/table was prepared to eliminate any frost action in the ground. In addition to the frost design calculations, two triaxial tests were conducted to evaluate the bearing capacity of the iron sand material. The limited test results indicated that, the bearing capacity of iron sand is similar to conventional sand both in terms of stiffness as well as permanent deformation behavior.]]></description>
      <pubDate>Mon, 03 Apr 2023 16:47:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/2145735</guid>
    </item>
    <item>
      <title>Enhancing the durability of concrete in severely cold regions: Mix proportion optimization based on machine learning</title>
      <link>https://trid.trb.org/View/2124490</link>
      <description><![CDATA[Compared with inland areas, the environment for concrete in severely cold regions is more harsh and includes ion erosion, changes in dry and wet conditions, low-temperature freeze–thaw cycles and other occurrences leading to surface damage to and the cracking of roads and bridges, which causes concrete structures to be unable to reach their service life due to insufficient durability. By optimizing the mix proportion (MP) of the materials used, the frost resistance and impermeability of concrete can be improved to enhance its durability. In this paper, the authors develop an intelligent prediction and optimization model of concrete durability (CD) based on a random forest (RF) model and NSGA-II, and a Pareto front of the optimal trade-off solutions can be obtained by using NSGA-II to perform the optimization. A final optimal solution, the one that is nearest to the ideal solution, is determined as the suggestion for decision-making. The research is verified by taking a key highway engineering project in the Plan for Revitalizing Northeast China as an example, and the results show that the following: (1) The key factors after screening are the water–binder ratio, cement content, coarse aggregate content, fine aggregate content, high-efficiency water-reducing agent and fly ash content. (2) In comparison with other machine learning algorithms, a filtered RF prediction model has high precision, the goodness of fit (R2) of the frost resistance and impermeability is higher than 0.95, and the root mean square error (RMSE) is less than 0.1. (3) After optimization, the chloride ion permeability coefficient of concrete is reduced by 47.9%, the relative dynamic elastic modulus (RDEM) is increased by 4.07%, and the cost is reduced by 2.4%. In summary, the proposed RF-NSGA-II intelligent hybrid optimization algorithm can improve the durability of concrete in severely cold regions while realizing the economic and environmental protection production of concrete to improve engineering safety performance and service life.]]></description>
      <pubDate>Tue, 28 Mar 2023 09:56:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2124490</guid>
    </item>
    <item>
      <title>Assessment of mechanical and thermal properties of foam glass aggregates for use in pavements</title>
      <link>https://trid.trb.org/View/1682667</link>
      <description><![CDATA[In cold regions, frost heave and bearing capacity loss during spring, induced by seasonal temperature variations, lead to several types of damages on the road networks. The use of FGAs as thermal insulation layer in flexible pavement structures contributes to increase in durability of the pavement and decrease in maintenance and rehabilitation costs. In this technique, FGAs control and limit frost penetration in the frost sensitive subgrade soil which help to decrease freezing and thawing impacts responsible for the bearing capacity loss on the roads and highways. In Quebec and Canada, extruded polystyrene (XPS) is widely used as the only standardized insulating material for pavement insulation. However, application of FGAs presents a double benefit, including environmental advantage by recycling waste glass as well as technical advantage by providing a lightweight, insulating and draining layer to strengthen the roads and highways against permafrost phenomenon. In the present research work, experimental studies including full-scale laboratory and field tests have been conducted to assess the physical, mechanical and thermal characteristics of FGAs when used as a lightweight insulating layer. The same experiments have been carried out on the structures containing natural aggregates and XPS panels as the two reference tests. The results demonstrated that FGAs have the potential of being used as a trusted insulating layer and can be considered as a suitable substitute for the XPS panels. Moreover, in this study a conceptual design chart has been proposed for Québec region illustrating FGA thickness with respect to frost depth. To develop this design chart, the software “Chaussée2” was utilized to conduct the simulations. The simulation results have been then calibrated using the field data obtained from three consecutive winters between 2015 to 2018.]]></description>
      <pubDate>Tue, 04 Feb 2020 14:58:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/1682667</guid>
    </item>
    <item>
      <title>Innovative Materials for Road Insulation in Cold Climates: Foam Glass Aggregates</title>
      <link>https://trid.trb.org/View/1434843</link>
      <description><![CDATA[Freezing and thawing cycles cause road network damages associated to differential heaving and bearing capacity loss during spring. As a result, deterioration of the ride quality, cracking of the asphalt concrete layer and finally, increased rutting and pothole formation are likely to occur. This leads to increased maintenance and higher rehabilitation costs. In order to improve the durability of the pavement, thermal insulation is used more and more in the province of Quebec. This protection technique limits frost penetration in the frost susceptible subgrade soil, thus reducing the associated damage and the rehabilitation costs. In Quebec and in Canada, extruded polystyrene is the material commonly used for pavement insulation. New alternative materials are now available, including foam glass aggregates made from recycled glass of various origins. Foam glass aggregates can be considered as lightweight and suitable for insulating granular material. This study will expose the state of knowledge on thermal insulation with cellular glass. It will also describe the results obtained from the tests performed in the laboratory and from monitoring an experimental road site during its first year of use. The test site is composed of three different sections build on frost sensitive soil: the first section is insulated with foam glass aggregates, the second is insulated with extruded polystyrene panels and the third is a conventional pavement structure without insulation. The results from the experimental site will be used to compare the thermal behavior and the performance of the three sections. Special attention will be given to the first section to gather the effect of foam glass aggregates integration on pavement structure. The thermal and performance data collected in-situ will be compared to those obtained in the laboratory. The result obtained from this new product will be used in the design methods for flexible pavements in cold regions.]]></description>
      <pubDate>Tue, 15 Nov 2016 16:51:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/1434843</guid>
    </item>
    <item>
      <title>Frost heave in highway tunnels in Nordland County, Norway</title>
      <link>https://trid.trb.org/View/1404670</link>
      <description><![CDATA[Two highway tunnels opened in the years 2005-2006 in Nordland County, Norway has suffered from frost heave and formation of lumps of ice on the road surface up to 3 kilometres into the tunnels. Norwegian Public Roads Administrations (NPRA) started an investigation program to find the reasons for this. This program included sampling of materials in the road structure, measurements of frost indexes and frost penetration into the tunnels, registration of the drainage system and studies of the construction plans and performance of the construction. These investigations showed that errors where made both in planning and construction of the tunnels leading to the problems. The reasons for the frost heaves were mainly that the frost affected areas was larger than estimated partly because of forced ventilation in one direction, inadequate drainage system because it was placed too shallow compared to the formation rock-bed, inadequate cleaning of the frost susceptible fines in the tray after blasting of the mica-rich bedrock and slightly frost susceptible materials in the sub-base where brought in. These tunnels are now being rehabilitated based on these findings by replacing the all the frost susceptible soil and placing of a new drainage system below the level of the formation rock-bed while also ensuring frost protection of the pipes by using XPS-plates. New tunnels in the northern region are now being built more robust with longer frost zones, cleaning of the fines in the tray and deeper drainage systems within the frost zones.]]></description>
      <pubDate>Thu, 21 Apr 2016 12:36:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/1404670</guid>
    </item>
    <item>
      <title>A new pavement design procedure for frost protection in seasonal frost areas</title>
      <link>https://trid.trb.org/View/1404602</link>
      <description><![CDATA[Differential frost heave and uneven degradation of flexible pavements surface profile in cold climate significantly affects the serviceability of these important civil engineering structures. Among the factors influencing this phenomenon, subgrade soils variability is documented as a significant parameter to consider, especially regarding differential frost heave. Subgrade soils variability may increase in urban area because of the buried utilities and the numerous cuts, both usually filled with granular materials. Therefore, past researches were revisited to implement a design methodology for frost heave protection of flexible pavements in northern environment based on the risk of differential frost heave caused by subgrade soils variability. Previous data were used to 1. Propose a relationship between the maximum pavement IRI, usually encountered at the end of the winter period, the design period and the subgrade soils longitudinal variability index, and 2. Quantify the effect of the replacement of in situ subgrade soils with granular fill on the coefficient of variation of frost heave. The relationship was used as a reference to identify allowable average frost heave based on subgrade soils variability conditions. This is specifically applicable in the urban context for which granular fills, and consequently supplementary induced soil variability, is the main factor contributing to the determination of the allowable frost heave. Working examples of various classes of urban pavements allowed obtaining allowable frost heave criteria that take into account subgrade soils variability, design period and maximum allowable roughness, which are also in good agreement with available data in the literature.]]></description>
      <pubDate>Thu, 21 Apr 2016 12:24:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/1404602</guid>
    </item>
    <item>
      <title>Flexible Pavement Design for Frost Protection Taking Into Account Subgrade Soils Variability</title>
      <link>https://trid.trb.org/View/1301779</link>
      <description><![CDATA[The serviceability of flexible pavements in northern environments is an important issue when the effect of frost heave is experienced at the surface of these structures. As frost heave is rarely uniform, the pavement roughness usually increases during winter due to differential frost heave. In this paper, a design methodology for the determination of allowable frost heave based on subgrade soils variability is proposed. The method also allows proposing allowable frost heave criteria based on the presence of buried utilities, which trenches are usually filled with materials non sensitive to frost, in the case of residential and arterial roads in the urban context. The allowable frost heaves are a function of subgrade soils variability, and therefore function of the risk of differential frost heave, and are in good agreement with data found in the literature. (A) For the covering abstract of this conference see ITRD record 201310RT334E.]]></description>
      <pubDate>Tue, 11 Mar 2014 10:57:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/1301779</guid>
    </item>
    <item>
      <title>Thermal monitoring of motorway tunnel insulation structures</title>
      <link>https://trid.trb.org/View/1290150</link>
      <description><![CDATA[In road tunnels in Finland, water and frost isolation lining is needed to ensure traffic safety due to the ground water leakage and freezing problem during winter time. Insulation also improves the stability of the rock mass around tunnels, since freezing - thawing phenomena can be avoided. Adequate and well positioned lining diminishes maintenance costs of the tunnel, since formation of icicles is avoided and roads do not become slippery due to frozen water drops. Typical lining consists of polyethylene sheets covered with shotcrete as fire protection. The lining is very costly so the dimensioning, both in length and thickness, must be done carefully and case by case. Adequate information of the temperature as well as insulation properties is needed for the dimensioning of the lining. This paper presents a development study to evaluate functioning of the isolation lining versus dimensioning done during design phase of seven motorway tunnels. The lining structures in the tunnels were thermo-mechanically modelled prior to construction. Based on the continuous temperature measurements in the tunnels and updating of the created model, new and valuable information is gained for next projects. With the new information obtained from this study, both construction and maintenance costs can be limited.]]></description>
      <pubDate>Wed, 29 Jan 2014 13:51:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/1290150</guid>
    </item>
    <item>
      <title>Frost protection and insulation for transportation facilities</title>
      <link>https://trid.trb.org/View/1185990</link>
      <description><![CDATA[This issue contains 5 papers concerned with frost protection and insulation for transportation facilities.  Specific topics addressed include:  polystyrene foam; extruded expanded polystyrene; insulation performance beneath roads and airfields; cellular plastic as railroad track insulation; and frost heave prevention.]]></description>
      <pubDate>Fri, 24 Aug 2012 05:58:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/1185990</guid>
    </item>
    <item>
      <title>Effect of Cement Content on Durability of Fly Ash-Carbide Slag Residue Concrete</title>
      <link>https://trid.trb.org/View/1110038</link>
      <description><![CDATA[Through the indoor experiments of the bending strength and the compressive strength at different contents and ages, the optimal cement and fly ash-carbide slag content were determined. The durability of optimal cement content residue concrete and pure residue concrete were systematically studied by related experiments and scanning electron microscopy (SEM). Combined with the actual construction in Three Gorges reservoir area, the durability was verified. The results show that when the optimal cement content is 150kg/m3 and the fly ash —carbide slag content is 350kg/m3, the impermeability, the frost resistance, the erosiveness resistance and the wear resistances of residue concrete are obviously improved, which can meet the pavement surface requirements of rural roads in the Three Gorges reservoir region. It also offers a valuable reference for environmental protection and rural road construction.]]></description>
      <pubDate>Mon, 08 Aug 2011 14:20:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/1110038</guid>
    </item>
    <item>
      <title>Technology Research of Non-Burnt Brick and Application to Highway Engineering</title>
      <link>https://trid.trb.org/View/1093532</link>
      <description><![CDATA[The climate and natural conditions are comparatively arid and in the western area of China. Many highways, passing through the desert fringe or hinterland are endangered by the wind and tignum is scarce along the roads. The non-burnt brick, being made of aeolian sand, utilizing cementations material has many advantages such as high strength, corrosion-resistance, water-fast, frost resistance, and so on. This paper summarizes the results of the experimental investigation on the non-burnt brick, which demonstrates that the brick used in road kerb and slope protection can not only minimize the engineering cost, but also decrease the sand erosion. The practice shows that the brick being made of aeolian sand used in road has a good effect on engineering economy and road protection. This provides a new kind of protective material for road construction in desert areas.]]></description>
      <pubDate>Tue, 22 Feb 2011 11:26:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/1093532</guid>
    </item>
    <item>
      <title>DIE ANLAGE EINER VERSUCHSSTRECKE FUER ASPHALTOBERBAU BEI BOEBLINGEN</title>
      <link>https://trid.trb.org/View/1080243</link>
      <description><![CDATA[ZUR KLAERUNG NOCH OFFENER FRAGEN HINSICHTLICH DER BEMESSUNG VON ASPHALTOBERBAU WURDE EINE VERSUCHSSTRECKE UNTER SCHWEREM VERKEHR UND UNGUENSTIGEN KLIMATISCHEN VERHAELTNISSEN ANGELEGT. DIE KONZEPTION DER VERSUCHSSTRECKE, DIE NEBEN ZWEI STANDARDISIERTEN BEFESTIGUNGSAUFBAUTEN WEITERE DREI NACH UNTERSCHIEDLICHEN KRITERIEN BEMESSENE ABSCHNITTE MIT ASPHALTOBERBAU ENTHAELT,  WIRD DARGELEGT UND ANLAGE SOWIE EINBAU GESCHILDERT. DAS GEPLANTE MESSPROGRAMM WIRD EINGEHEND BESCHRIEBEN UND EINE UEBERSICHT UEBER DIE INSTRUMENTIERUNG DER STRECKE GEGEBEN. (A).]]></description>
      <pubDate>Sun, 21 Nov 2010 18:02:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/1080243</guid>
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