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    <title>Transport Research International Documentation (TRID)</title>
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
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    <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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      <title>Procedures for identifying hazards in component materials for asphalt</title>
      <link>https://trid.trb.org/View/916296</link>
      <description><![CDATA[The use of secondary materials in road construction seems to be considered by some to be the preferred method for their disposal. However, such materials need to undergo a wide range of investigations to check their suitability, from simple to expensive, because of the distinct properties of the material at source. Various strategies to promote the use of by-products could be considered for adoption, but are not the subject of this investigation. The overall aim of the task within the SAMARIS project was to produce a methodology of testing alternative components for potential hazards. There are several materials known to have been used in pavements that require care, should such pavements be used for recycling. However for any procedure to be general and to allow for new potential hazards to be considered, the circumstances that maximise the risk during the extraction of the old pavement together with the manufacture, paving and use of the recycled material have to be included in the procedure. A procedure was developed around two known hazardous component materials and four more general situations with suitable tests being identified to check for them. For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:03:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/916296</guid>
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    <item>
      <title>Review and analysis of the variations in ageing rates of equivalent grade road bitumens based on colloidal structure. Part 2. Experimental investigation</title>
      <link>https://trid.trb.org/View/916295</link>
      <description><![CDATA[From a performance point of view, bitumen is one of the most important constituents of asphalt mixtures. The quality and properties of bitumen depend largely on its chemical composition. Evidence obtained from laboratory oven ageing tests suggests that bitumens having the same grade, but originating from different crudes, can age quite differently. This evidence is further supported by data from laboratory compacted asphalt mixtures. In the second part of this study, bitumen samples having several grades, from Middle Eastern and Venezuelan sources, were tested in their virgin and oven aged conditions. All the samples were fractionated into their saturates, aromatics, resins and asphaltenes using TLC-FID analysis. The results show consistent differences in the percentage saturates and aromatic hydrocarbon fractions between Middle Eastern and Venezuelan bitumens. On the other hand, ageing seems to have a different effect on the saturate fractions of the two bitumen types. The colloidal instability coefficient was shown to be a useful tool in highlighting differences between the two bitumen sources. For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:03:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/916295</guid>
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    <item>
      <title>Review and analysis of the variations in ageing rates of equivalent grade road bitumens based on colloidal structure Part 1: Critical review</title>
      <link>https://trid.trb.org/View/916294</link>
      <description><![CDATA[From a performance point of view, bitumen is one of the most important constituents of asphalt mixtures. The quality and properties of bitumen depend largely on its chemical composition. Evidence obtained form laboratory oven ageing tests suggests that bitumens having the same grade, but originating form different crudes, can age quite differently. This evidence is further supported by data from laboratory compacted asphalt mixtures. The first part of this study reviews in some detail the effect of the chemical composition of penetration grade bitumens on ageing performance. Simple explanations of the ageing mechanisms are presented in the paper primarily based on chromatographic separation techniques. For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:03:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/916294</guid>
    </item>
    <item>
      <title>Back analysis of alternative materials used in roads</title>
      <link>https://trid.trb.org/View/916293</link>
      <description><![CDATA[Since the 1990s the issue of road construction with wastes and secondary materials has led to various studies and programmes aiming at clarifying its technical, economic and environmental feasibility. Indeed, alternative materials used within the road structure are submitted, for long term periods, to mechanical and thermal stresses, soaking and drying effects, both of which are responsible for physical and chemical changes. Consequently, for the same kind of road application, the behaviour of an alternative material can be strongly different from one place to another according to the local conditions. Although it is a crucial point, back analysis of roads made of alternative materials has not yet really been achieved. As today very few data at road scale are available, a set of French examples was collected and studied. The analysis of these cases is performed in order to allow for proposing typical use scenarios, considering both the material reactivity and the use conditions. 17 cases documented with reports and articles were obtained. Among them, both classical and experimental roads were found, providing mechanical and / or environmental results. The analysis of each case was carried out thanks to a specification sheet describing the road structure, the material, the local factors and the mechanical and environmental responses of the material and of the structure. The content and use of this specification sheet is illustrated through the description of some contrasted cases. For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:03:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/916293</guid>
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    <item>
      <title>Pavement solutions for the urban environment</title>
      <link>https://trid.trb.org/View/916292</link>
      <description><![CDATA[Mouchel Parkman in partnership with Birse Civils Ltd were appointed in2004 by a UK Metropolitan Borough Council to undertake a works rehabilitation programme, the aims of which were to raise the profile of the borough by investing UK Government Prudential funding to the value of £5M across the road network. Pavement condition surveys and additional site investigations were carried out and innovative pavement designs were explored, including the retention of the existing pavement layers and their residual strength. The rehabilitation options considered include inlay using flexible construction in order to maintain kerb levels, or inlay using flexible construction plus raising kerbs to enable 40mm or 60mm resurfacing of the footways. Recycling of existing materials is discussed.  For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:03:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/916292</guid>
    </item>
    <item>
      <title>Bitumen bound construction units utilising only recycled and waste materials as aggregates</title>
      <link>https://trid.trb.org/View/916291</link>
      <description><![CDATA[The preliminary experimental results obtained during the development phase of a new construction material area described. The material is composed entirely of recycled and waste aggregates and binding agents from selected bitumens. The material can be potentially used in masonry construction and block paving. The utilisation of recycled and waste materials in construction applications is an effective method to help assist the UK Government with its waste management plan. The product presented in this paper and the manufacturing methodology will help reduce the quantity of disposed waste, the expenditure for treatment and primary aggregate extraction. Four main waste materials were used in this study, namely crushed glass, incinerator bottom ash (IBA), pulverised fuel ash (PFA) and incinerated sewage sludge ash (ISSA). Crushed glass and IBA can be incorporated as either coarse or fine aggregates in the mix. They are combined with PFA or ISSA, which act as fillers before they are mixed with bituminous binders. A standard 50 penetration grade bitumen and a bituminous emulsion were used in these tests. Depending on the type of binder used, test samples were manufactured using either a hot or cold process. After the samples were compacted into shape, they were oxidised by heat curing. This curing regime converts the bitumen from a thermo-plastic binder into a brittle material which is then significantly more stable at normal working temperatures and stresses. The material properties of the samples are also greatly enhanced by this conversion. A number of properties of the samples were measured to confirm their performance in relation to clay and concrete block masonry products. For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:03:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/916291</guid>
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    <item>
      <title>Geotechnical specifications for sustainable infrastructure</title>
      <link>https://trid.trb.org/View/916290</link>
      <description><![CDATA[The specification of the materials and methods used in earthworks and foundations for highways, railways and airfield runways can be approached in several ways. As a result of the sustainability agenda there is a need to use specifications that make best use of material properties, and a performance-based specification may be considered the best way to facilitate this. The functional requirements of a performance-based specification for UK highway foundations are considered. The (recently researched) performance-based specification for UK highway foundations is explained, demonstrating the steps to its development, determination of the engineering requirements, suitable target values and the potential construction-related implications. It is shown that performance-based  specifications offer the advantage of better incorporation of the principles that underpin sustainable construction but also require a fuller understanding of material behaviour for their development and implementation. However, contractural issues and implications for construction need to be considered if a full performance-based approach is to be successfully adopted. It is considered in the UK that a staged implementation of a performance specification is necessary to permit the gaining of experience of both the process and the field measurement methods, some of which are relatively novel, and to reduce the risk of contractual disputes and thus a negative reaction from the industry. For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:03:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/916290</guid>
    </item>
    <item>
      <title>Recycling porous asphalt</title>
      <link>https://trid.trb.org/View/916289</link>
      <description><![CDATA[Porous asphalt is the preferred asphalt for Dutch motorways because of its water draining capabilities as well as its noise reduction. Because of its specific properties, amongst others the mineral grading, porous reclaimed asphalt pavement cannot be used in dense asphalt mixtures in the same quantities as regular RAP. If recycled, only 25-50% of the total RAP can come form porous asphalt. At the same time, the reuse of RAP and / or PRAP in base courses is decreasing due to the availability of many other secondary materials and a decreasing number of new roads. Furthermore reconstruction usually involves replacing only the top layer (with new porous asphalt). The net result is that more PRAP is generated than is used. In the past several attempts have been made to use porous asphalt granulates in new porous asphalt. For varying reasons these attempts have not been very successful. With the increasing surplus of PRAP, Koninklijke Wegenbouw Stevin picked up the challenge to recycle PRAP in porous asphalt. Based on tests and trial sections, it was concluded that porous asphalt containing 30-50% PRAP was possible without extra pre-treatment and with economic and environmental benefits. For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:03:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/916289</guid>
    </item>
    <item>
      <title>A life cycle approach to the selection of construction materials</title>
      <link>https://trid.trb.org/View/916288</link>
      <description><![CDATA[Materials for construction have been selected to the lowest cost alongside engineering requirements. Yet increasing attention is given to the environmental performance of the construction process and end products. This becomes more obvious when efforts are called on by a range of stakeholders to use alternative materials. The many aspects it could represent include design for more durable products, lower life-time costs and environmental impacts. Life Cycle Assessment (LCA) emerges as a potential tool to analyse the environmental impacts of a  product of a process throughout its lifetime, and to report to interested groups for communication. This study reviews the relevance of LCA to the construction and asphalt industry, and the growing consensus regarding the list of key indicators. It also highlights the existing LCA procedures that can be adapted to this sector, and identifies relevant LCA models and databases that exist worldwide to help facilitate the analysing process. A case study is provided about the LCA of a resurfacing project earlier this year at Wolverhampton by Aggregated Industries UK Ltd. Intending to provide a robust and objective assessment technique, this paper also recognises that the life cycle approach has its limits, and identifies areas that need further development. To support an integral sustainability strategy, the environmental assessment must be supplemented by technical and economic studies. For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:03:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/916288</guid>
    </item>
    <item>
      <title>Effect of silica fume and fly ash on fatigue and impact strength of fibre-reinforced concrete</title>
      <link>https://trid.trb.org/View/916287</link>
      <description><![CDATA[The utilisation of by-products such as silica fume and fly ash in the production of concrete produces concrete with desirable performance characteristics. However, these materials can also impair the ability of concrete to resist dynamic loading, a property that can be restored using fibre reinforcement. This paper reports the results from a programme of laboratory research, which has been conducted to investigate the effect of silica fume and fly ash on the fatigue strength and impact resistance of fibre-reinforced concrete. In this work, six mixtures were investigated. The control mix was produced without fibre or cement replacement materials. The other five mixes were reinforced with 1% (by volume) steel fibres. The effects of fly ash and silica fume were investigated at two replacement levels on a weight-to-weight basis. For fly ash, the replacement levels were 25% and 50%, whereas the replacement percentages for silica fume were 5% and 10%. The results suggested that the effect of steel fibre on the flexural fatigue strength was more significant than the effect of the cement replacement materials. The use of silica fume and fly ash slightly improved the flexural fatigue behaviour. As a conservative approach, it was concluded that the fatigue strength of mixes containing silica fume or fly ash is at least comparable to that of Portland cement FRC. The use of steel fibre had a negligible effect on the first-crack impact resistance, yet it enhanced the ultimate impact resistance by more than 200%. The mix including silica fume exhibited a 50% increase in both first-crack and ultimate impact resistance of the FRC. The effect of fly ash on the impact resistance was insignificant. For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:02:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/916287</guid>
    </item>
    <item>
      <title>A material performance test for pavement foundations</title>
      <link>https://trid.trb.org/View/916286</link>
      <description><![CDATA[The current pavement foundation process in the UK is base don the California Bearing Ratio, coupled with a method specification based on past experience and proven performance. This provides a trusted empirical indicator of adequate performance. The wider use of marginal and recycled / secondary aggregates is necessary for achieving industry sustainability targets. There is also a move towards analytical design, based upon the fundamental material performance properties of elastic stiffness and shear strength. Analytical design combined with performance based specifications, potentially allow any materials that are fit for purpose. This approach, however, requires field measurements to confirm the assumed design performance is achieved. In addition, performance data for analytical design are required, before the materials are used to ensure confidence in their likely behaviour and hence in the design. A large scale laboratory assessment test has been developed to measure the performance of coarse granular materials. The test utilises the same portable devices used to measure performance in the field, thus providing directly comparable results. This paper discusses the development of the laboratory performance test, its use and role in the wider context of the design process, and what advantages it brings to the highway construction industry. For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:02:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/916286</guid>
    </item>
    <item>
      <title>Unbound crushed concrete in high volume roads - a field and laboratory study</title>
      <link>https://trid.trb.org/View/916285</link>
      <description><![CDATA[In Norway, recycled concrete aggregate has recently been introduced in design codes for road construction, including material specifications. A number of field projects have revealed good functional properties (proven suitability) despite the fact that the mechanical properties of the materials in many cases do not comply with specifications concerning mechanical strength. Traditional test methods for mechanical properties are clearly not suitable for these kinds of materials. A proper evaluation should therefore be based on performance-related (functional) tests. This paper discusses these field-lab contradictions with reference to a field trial at highway E6 south of Trondheim where crushed concrete was used as a sub-base layer in a pavement designed for over 10000 vehicles per day. The road was constructed in 2003-2004, and will be followed up by frequent bearing capacity, rutting and evenness measurements. Preliminary results for these properties appear to be very promising. The main objective of this program is to facilitate more frequent and environmentally safe applications of recycled materials in road construction. For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:02:54 GMT</pubDate>
      <guid>https://trid.trb.org/View/916285</guid>
    </item>
    <item>
      <title>Asphalt reinforcement - COST action 348</title>
      <link>https://trid.trb.org/View/916284</link>
      <description><![CDATA[This article describes the COST Action 348 working group to enhance the process of material assessment and design as well as to develop appropriate structural design methods and measurement techniques for the reinforcement of pavements with steel meshes and geosynthetics. The programme of the working group and its five work packages are described. Plans for design guides and testing standards at a European level and recommendations for installation on site, for in situ testing and placement of reinforcement are proposed. For the covering abstract  see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:02:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/916284</guid>
    </item>
    <item>
      <title>Evaluation of roller compacted concrete pavement with bottom ash by ultrasound measurements - an experimental study</title>
      <link>https://trid.trb.org/View/916283</link>
      <description><![CDATA[The utilisation of waste materials in roller compacted concrete (RCC) was investigated in the laboratory with respect to the use of coal bottom ash produced by a Brazilian thermal power plant. The intention is to minimise the environmental impact related to the disposal of of bottom ash. This non-standardised ash was used to replace the natural sand content in RCC mixtures. RCC mixtures with 80 and 120kg/m3 of cement were proportioned by soil compaction methods. Mixtures with bottom ash as natural sand replacement were prepared for each cement content. Compressive strength and flexural strength were evaluated for each mixture at 28  and 90 days. Ultrasound measurements were performed at 3, 7, 14, 21, 28, 56 and 90 days to assess the development between p-wave speed over time, as well as the relationship between p-wave speed and the mechanical properties for each mixture. The results indicate the feasibility of applying coal bottom ash to RCC mixtures. Ultrasound measurements revealed a unique relationship between p-wave speed and the mechanical properties, indicating that ultrasound may be a useful tool to monitor the development of RCC properties over time on field applications. For the covering abstract of this conference see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:02:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/916283</guid>
    </item>
    <item>
      <title>Conway Dartford recycling facility - a UK showcase for aggregate recovery</title>
      <link>https://trid.trb.org/View/916282</link>
      <description><![CDATA[Facilities at F M Conway Ltd's recycling plant at Dartford, Kent, are described. These include a 14-strong fleet of unconventional mobile concrete batch mixer lorries and a special high-pressure water washing plant for cleaning and screening up to 80t/h of dirty raw feed material into reusable sand and aggregate. This investment follows on from the purchase in 2001 of a conventional 350t/h crushing and screening plant, and 2002 of a mobile Foamix plant, which has the ability to produce either cement or bitumen stabilised road base materials. This specialised equipment was also joined in the spring of 2004 by a unique purpose-built plant which will recycle up to 95% drainage waste from its Cleansing Division activities and transfer the recovered grit and sand to the washing plant for cleansing and subsequent use in concrete production. The 14-acre Dartford Recycling facility is believed to be one of the largest and most advanced in Europe. For the covering abstract see ITRD E145817]]></description>
      <pubDate>Fri, 23 Apr 2010 11:02:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/916282</guid>
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