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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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    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>Effect of natural zeolite in enhancing rutting behaviour of bituminous binder</title>
      <link>https://trid.trb.org/View/2618009</link>
      <description><![CDATA[In the current scenario, the pavement industry focuses on incorporating sustainability and use locally available materials for road construction. Generally, road construction done using Hot Mix Asphalt requires high working temperature ranges. Warm Mix Asphalt is one of the ways that can be used to reduce the working temperature by adding suitable modifiers. This study aims to investigate the effect of locally available materials such as Natural Zeolite (NZ) to reduce the working temperature of mixes and in addition improve the performance of the pavement. Four dosages of NZ were used and the base binder was Viscosity Grade 30 (VG30).The modified binder was subjected to short-term aging and was tested for rutting performance using Multiple Stress Creep Recovery. With a low Jₙᵣ value of 0.1234 and 0.1364 along with higher value of percentage recovery of 31.77 and 25.45 for both stress levels of 0.1kPa and 3.2kPa respectively, it was concluded that adding 5% NZ to VG30 effectively enhanced pavement rutting performance and promoted sustainability.]]></description>
      <pubDate>Mon, 09 Feb 2026 13:55:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2618009</guid>
    </item>
    <item>
      <title>Experimental and predictive approach for volcanic ash geopolymer in the stabilisation of expansive subgrade</title>
      <link>https://trid.trb.org/View/2643572</link>
      <description><![CDATA[This study investigated the stabilisation of expansive subgrades with volcanic ash (VA) geopolymer through a series of experimental tests, including unconfined compressive strength (UCS), water absorption, swelling potential, along with SEM and EDX analyses. The performance of the soil specimens was then evaluated in comparison with the road subgrade material requirements and ordinary Portland cement (OPC). Moreover, a new predictive model was developed using gene expression programming (GEP) to estimate the UCS values. The results revealed that VA geopolymer-stabilised specimens exhibited superior mechanical performance compared to those improved with OPC. A considerable decrease of approximately 98% in swelling and 95% in water absorption was detected with stabilisation. Microstructural analysis showed a denser and more compact soil matrix with VA incorporation. VA geopolymer stabilisation minimised CO₂-e emissions by approximately 44% in comparison with OPC. Additionally, the GEP-based prediction model exhibited superior performance in the prediction of UCS values with low error. A multi-factor analysis of variance (ANOVA) was also carried out, and Pearson correlation coefficients were constructed to statistically evaluate the experimental results. The results revealed that the bulk density, swelling, water absorption and UCS parameters were predominantly affected by the molarity and curing duration.]]></description>
      <pubDate>Sat, 17 Jan 2026 11:41:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2643572</guid>
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    <item>
      <title>Cement Kiln Dust with Fine Volcanic Ash as Substitute Fillers for Hot Mix Asphalt</title>
      <link>https://trid.trb.org/View/2553014</link>
      <description><![CDATA[Waste and by-product materials are often used as substitutes for raw materials in asphalt mixtures to lessen building costs, minimize environmental problems, and protect natural resources. This study investigates the feasibility of employing two kinds of ashes, fine volcanic ash (FVA) and cement kiln dust (CKD), which are abundantly available in various regions of Yemen, as substitute hot mix asphalt filler (HMA) for conventional fillers. A traditional filler, basalt filler (BF), was partially and totally replaced at different percentages. FVA replaced 15%, 30%, 45%, 60%, and 100% by weight of the filler. CKD replaced the traditional filler with 25%, 50%, 75%, and 100% by weight of fillers as a partial replacement. The total replacement of traditional fillers includes 20% CKD + 80% FVA, 40% CKD + 60% FVA, 60% CKD + 40% FVA, and 80% CKD + 20% FVA. The evaluation of the planned HMA was done using conventional mechanical and volumetric characteristics. Marshall stability, direct compression (DC) tests, and indirect tensile strength (ITS) were employed to evaluate the influence of FVA with CKD fillers on the asphalt mixture’s mechanical characteristics. The outcomes of the experiment demonstrated that 60% CKD + 40% FVA was used instead of the traditional mineral filler. A novel HMA was introduced, demonstrating enhanced stability, increased bulk density, decreased voids filled with bitumen (VFB), and lower flow compared to the mixture used as a control. Results showed that FVA and CKD may respectively substitute 30% and 75% of the BF. The ITS and the DC exhibited an increase. Therefore, incorporating CKD and FVA as fillers in is a sustainable solution that enhances performance, durability, and environmental benefits in asphalt construction.]]></description>
      <pubDate>Fri, 26 Sep 2025 13:40:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2553014</guid>
    </item>
    <item>
      <title>Dynamic behavior of volcanic ash of Tajogaite (La Palma, Canary Islands, Spain)</title>
      <link>https://trid.trb.org/View/2583419</link>
      <description><![CDATA[The dynamic characterization of soils is essential for the analysis of their dynamic behavior, soil-structure interaction under seismic loading, seismic design of the constructions to be built on them, soil failure and liquefaction analysis under seismic loading, etc. Dynamic laboratory tests are usually performed over reconstituted sandy material, and sometimes over undisturbed sandy specimens. In this paper the performance of a volcanic sandy material in its fresh natural state, without subsequent consolidation and cementation, is studied to determine its strain dependent shear modulus and damping ratio under range of shear strains considering its location in affected seismic areas. In this study, reconstituted samples in their dry state under different initial relative densities and applied vertical pressures are examined by densification tests performed by cyclic direct simple shear test analyzing vertical strains, shear modulus and damping ratios. The highest densification is observed during the application of the first 10 to 100 cycles. In general, the lowest shear modulus values are obtained for low values of applied vertical stress, and a decrease of damping ratio is observed with the increase of the application of cycles. Also, resonant column tests are performed under different effective confining pressures, observing the general trend of degradation of normalized shear modulus and the increase of damping ratio for the increase of shear strains, with the linear initial relation of shear modulus with shear strains in the range of small strains. The comparison of this non-linear dynamic behavior is performed to the usually applied relations for ordinary sandy materials, providing satisfactory adjustment in this case.]]></description>
      <pubDate>Thu, 18 Sep 2025 09:47:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/2583419</guid>
    </item>
    <item>
      <title>‘All Four Engines Have Failed’: A qualitative study of the health impacts, reactions and behaviours of passengers and crew onboard flight BA009 which flew through a volcanic ash cloud in 1982</title>
      <link>https://trid.trb.org/View/2551398</link>
      <description><![CDATA[This study investigated the experiences, health impacts and behaviors of passengers and crew onboard British Airways flight BA009 which flew through a volcanic ash cloud from Mount Galunggung, Indonesia, in 1982. In addition to secondary data sources, including a book published by one of the passengers, 18 semi-structured interviews were completed (14 passengers, 2 flight crew and 2 cabin crew) which were video recorded and transcribed verbatim. Data were analyzed using reflexive thematic analysis to examine the experiences, behaviors, and actions of those onboard, and the health impacts of exposure to volcanic emissions. The analysis identified five key themes which explain how people onboard flight BA009 responded: 1) Responsibility, 2) Airmanship and prior knowledge of aviation, 3) Upbringing and cultural background, 4) Faith and 5) Behavior of the crew. The study found few physical health impacts associated with the exposure to the ‘smoke’ and, despite individual cases of distress, there was no mass panic onboard the aircraft. The findings highlight valuable information on passenger and crew behavior in aviation crises, the risks of volcanic ash clouds to aviation, and have practical implications for aviation disaster management, planning and communication.]]></description>
      <pubDate>Wed, 20 Aug 2025 11:57:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/2551398</guid>
    </item>
    <item>
      <title>Development of a Type IP Cement Supplementary Report 5: Feasibility of Mining of Selected Pozzolans</title>
      <link>https://trid.trb.org/View/2519067</link>
      <description><![CDATA[A detailed assessment of the mineability of ten potential locations of pozzolans was made. The deposits are all volcanic ash beds within the Lakota Formation, a cretaceous sedimentary rock which crops out as a hogback, which encircles the Black Hills. The most favorable deposit is located about 10 miles south of the Cement Plant at Rapid City. There is very little overburden. The deposit is over 30 ft thick and could produce 1 million tons from an area less than 10 acres.]]></description>
      <pubDate>Mon, 24 Mar 2025 12:27:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2519067</guid>
    </item>
    <item>
      <title>Development of a Type IP Cement Supplementary Report 1: Investigation of Locally Available Natural Pozzolans</title>
      <link>https://trid.trb.org/View/2519071</link>
      <description><![CDATA[A reconnaissance survey of potential sources of pozzolans within 100 miles of Rapid City resulted in the selection of 26 sites. Most of these sites are volcanic tuffs of shales. Pozzolanic activity index data show that the Pierre Shale, "fire clay" from the Lakota Formation and the Rockyford Ash are the most suitable. A detailed geologic description indicates that the most favorable units are volcanic ash beds typically mixed with fine-grained terrestrial sediments. Chemical analyses on 9 samples by ICP spectroscopy and the scanning electron microscope indicate that silica is high, ranging from 56 to 80%, and sodium and potassium are low. A mineralogical study by x-ray diffraction shows that the predominant minerals are quartz and clay. The Rockyford Ash surprisingly showed 50% of the zeolite mineral clinoptilolite. Expansion tests show that the Rockyford Ash, Lakota fire clay, and Pierre Shale have the most promising pozzolanic qualities.]]></description>
      <pubDate>Mon, 24 Mar 2025 12:27:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2519071</guid>
    </item>
    <item>
      <title>Development of a Type I (PM) Cement</title>
      <link>https://trid.trb.org/View/2519070</link>
      <description><![CDATA[Alkali-silica reactivity (ASR) produces a major problem in concrete structures. This report presents an experimental investigation to identify a natural pozzolan and to determine the optimum quantity that can be blended with cement to produce a Type I (PM) cement for inhibiting the ASR. For comparative evaluation a Class F fly ash has also been investigated along with the pozzolans. Two methods, ASTM P214 and C227 were adopted for assessing the effectiveness of the pozzolans in controlling the ASR. Three percentages of 10%, 20% and 30% replacements of cement with fly ash were investigated. A total of 30 natural pozzolans were collected from the selected sites. Their chemical and mineralogical compositions and some physical properties, such as fineness and density, were determined. The strength activity test (ASTM C311) was used in eliminating the pozzolans that would adversely affect the strength of concrete. Based on this test, ten pozzolans were selected for detailed study. The ASR expansions measured using the ASTM P214 test method had shown that two pozzolans were more effective than the Class F fly ash in inhibiting the ASR expansion. This report also presents an extensive experimental investigation to evaluate the performance characteristics and physical properties of the selected natural pozzolan blended cements, cement mortars and cement concretes. There was no significant difference in the physical properties of pozzolan blended cements, cement mortars and cement concretes when compared with those of corresponding unblended cements, mortars and concretes. It is economically feasible to mine the selected pozzolans from the volcanic ash beds within the Lakota Formation. The most favorable deposit is located about 10 miles (16 km) from the cement plant at Rapid City.]]></description>
      <pubDate>Mon, 24 Mar 2025 12:27:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2519070</guid>
    </item>
    <item>
      <title>Shape quantification of volcanic cinders and the influence of particle shape indexes on accumulation characteristics</title>
      <link>https://trid.trb.org/View/2491342</link>
      <description><![CDATA[Volcanic cinder is a low-cost subgrade fill material in East Africa. A reluctance to use volcanic cinders for subgrades in the past has stemmed from the fact that the compactness is substandard and variable. Considering the irregular shape of volcanic cinders, the compactness can be improved by controlling particle shapes. The shape feature can be described from the macro-meso-microscopic scales through the improved algorithms of shape indexes, namely elongation (EI), roundness (Rd), and roughness (Rg). The shape indexes were calculated based on 2D contours of 1000 volcanic cinder particles, and the influences of shape indexes on accumulation behaviors are explored from macro-mesoscales through the discrete element method (DEM). The shape indexes of volcanic cinders are normally distributed, and EI has the widest variation range. The mesoscale index Rd has an interval effect on compactness and coordination number, whereas they are nearly unaffected by the microscale index Rg. The effect of elongation on particle accumulation behavior is stronger than roundness and roughness. Compactness is positively correlated with EI, and the force-fabric anisotropy degree weakens with increasing EI. Studies of shape quantification provide data reference for improving the utilization rate and accumulation compactness, which promotes the application of volcanic cinders in subgrade constructions.]]></description>
      <pubDate>Sun, 02 Mar 2025 16:07:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2491342</guid>
    </item>
    <item>
      <title>Evaluation of Impact of Volcanic Ash on Railway Electric and Signal Equipment and Proposal for Utilizing Information on Ash Fall</title>
      <link>https://trid.trb.org/View/2458865</link>
      <description><![CDATA[Volcanic ash fall can seriously affect railway operations by causing problems such as track circuit shunting malfunctions and decrease in insulation performance of insulators. In this study, the authors experimentally investigated volcanic ash conditions that cause these problems. Results allowed them to clarify that 0.05 mm thick volcanic ash causes shunting malfunction, and that 1.2 mm thick volcanic ash containing saline water causes insulator flashover. Based on these results, the authors propose preventive actions which railway companies can implement to mitigate the effects of ash fall, using public information on eruptions.]]></description>
      <pubDate>Tue, 03 Dec 2024 17:10:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2458865</guid>
    </item>
    <item>
      <title>Chemical, mineralogical and geotechnical properties of volcanic ash of Tajogaite (La Palma, Canary Islands, Spain)</title>
      <link>https://trid.trb.org/View/2410810</link>
      <description><![CDATA[Volcanic eruption at La Palma island (Tajogaite, 2021) has produced tons of volcanic ash as natural sediments spread all around the island covering existing crops, roads, embankments, buildings, etc., by that way producing damage to environment. For the rehabilitation and reconstruction of island, and its application to adjacent areas, it is practical and economical to employ these volcanic ashes as construction material being encountered in abundant volume, and by that way could be considered as a resource material instead as a waste material, reducing necessary volume of landfills for its deposition. This paper defines the investigation of chemical, mineralogical and geotechnical properties of these deposited materials for its possible reuse by that way providing solution for its recovery. These young volcanic ashes are studied in its fresh natural state, prior to consolidation and cementation has taken place for its chemical, mineralogical and geotechnical characterization. Volcanic ash of Tajogaite is of a poorly graded sandy nature having difficulties for its compaction, having low improvement of relative density by the application of standard compaction methods. Mineralogy analysis indicates it is rich in silica, iron, calcium and alumina oxide, although being necessary the addition of mineral additives for its alkali-activation. Geotechnical characteristics of different samples vary depending on the sampling site, being resistance parameters determined by direct shear test (friction angle 30° to 34°) and deformational properties defined by one-dimensional consolidation test considered low values as of loose sand materials (deformation modulus range from 20 to 40 MPa).]]></description>
      <pubDate>Fri, 06 Sep 2024 09:28:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/2410810</guid>
    </item>
    <item>
      <title>Cement-Stabilized Granular Volcanic Ash Materials for Construction of Low-Traffic Roads in Yemen</title>
      <link>https://trid.trb.org/View/2334175</link>
      <description><![CDATA[Granular volcanic ash (GVA) is a volcanic activity material with low density, high porosity, and other undesirable properties that must be improved prior to use in any construction. This material can be considered an alternative for use in road building, given its availability in many locations and in large quantities in Yemen. This article aims to investigate the potential use of GVA for the construction of roads in Yemen when treated with cement stabilizer. Two types of GVA materials with different colors were selected and referred to as red and black GVA materials. Tests performed included the unconfined compressive strength (UCS), compaction, indirect tensile strength (ITS), wetting–drying durability test, and ultrasonic pulse velocity (UPV) test for samples curried for 7 and 28 days. For each GVA–cement mixture, the cement content varied as 2%, 5%, and 8% by dry weight of GVA. Test results revealed that the compaction energy applied during sample preparation led to a significant reduction in the finesse modulus for red and black coarse GVA materials, with reductions of 10% and 23%, respectively. In addition, the cement content and curing period had a significant effect on UCS, ITS, and UPV for cement-treated GVA. The applicable quantity of cement required stabilizing GVA and achieving the base course specification for strength and durability criteria in flexible pavement with low traffic is 8% cement.]]></description>
      <pubDate>Mon, 05 Feb 2024 09:35:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2334175</guid>
    </item>
    <item>
      <title>Preparation and rheological performance analysis of volcanic ash and metakaolin based geopolymer grouting materials</title>
      <link>https://trid.trb.org/View/2167175</link>
      <description><![CDATA[This study investigated the possibility of using volcanic ash and metakaolin (MK) to prepare road grouting materials. The effects of different contents of MK and water glass(WG) on the mechanical properties, setting time and rheological properties of the materials were investigated separately. The materials science testing methods were also used to observe the reaction mechanism of the geopolymer products. The test results showed that the compressive strength increased with the content of MK and SS. The average flow curve of geopolymer grouts fitted the Bingham model. The multilayer lamellar microstructure of MK increases the rheological parameters of the pastes. While the WG suspends VA and MK particles, which reduces the rheological parameters of the pastes. It can be concluded from the results of microscopic experiments that the MK reduces side reactions as well as sodium by-products, while WG produces more silica-aluminate filling the voids which enhances the compressive strength.]]></description>
      <pubDate>Sun, 15 Oct 2023 17:36:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/2167175</guid>
    </item>
    <item>
      <title>Deformation and critical dynamic stress for compacted volcanic ash subjected to monotonic and dynamic loads</title>
      <link>https://trid.trb.org/View/2047911</link>
      <description><![CDATA[Volcanic ash is widespread in volcanic areas and is considered as a potential construction material. Therefore, volcanic ash can be used as subgrade material when building highways and railways in volcanic areas. However, there is limited research on the critical dynamic stress as well as deformation characteristics of volcanic ash under dynamic load. The Global Digital System (GDS) monotonic triaxial tests and dynamic triaxial tests are presented in this paper to quantify the critical dynamic stress as well as deformation characteristics of volcanic ash subjected to monotonic and dynamic loads. The critical dynamic stress and deformation of volcanic ash are affected by stress level, water content and dynamic stress amplitude. Under monotonic loads, the strength of volcanic ash decreases with increasing water content and increases with increasing confining pressure. The deformation of volcanic ash exhibits strain softening behavior which is enhanced with increasing water content and weakened with increasing confining pressure. According to the shakedown theory, the patterns of accumulative plastic strain for the volcanic ash under different dynamic stress amplitudes are classified into three categories, named plastic shakedown, plastic creep, and incremental collapse. This study redefines the shakedown limits for volcanic ash based on the shakedown theory. The adoption of new shakedown limits provides more accurate descriptions of deformation characteristics at different stress levels, water contents and dynamic stress amplitudes. Based on the new shakedown limits, this paper presents empirical models for the calculation of critical dynamic stress for volcanic ash shakedown limits using regression analysis. As a contribution to the literature and potential engineering applications, the proposed models may provide theoretical significance for the subgrade state evaluation.]]></description>
      <pubDate>Fri, 23 Dec 2022 14:07:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/2047911</guid>
    </item>
    <item>
      <title>Applying a Mt. Mazama Volcanic Ash Treatment as a Trail Accessibility Improvement</title>
      <link>https://trid.trb.org/View/2081510</link>
      <description><![CDATA[A procedure has been developed for implementing a topically applied Mt. Mazama volcanic ash trail surface amendment for improving trail firmness and stability. This project involved implementation of previously conducted Mt. Mazama volcanic research by applying a Mazama Ash and Portland Cement solution over a 0.2-mile section of the Geo Trail at the Oregon Institute of Technology Klamath Falls campus. Testing was performed to verify ideal Ash-to-Cement-to-Water ratios. A procedure was developed and applied for batching and mixing the dry materials on-site, spreading and integrating the dry material with the existing trail surface, and wetting and compacting the surface. After the pilot application, visual inconsistencies were observed in the treated trail surface. Firmness and stability were measured at different locations along the treated trail surface and on the untreated surface with a rotational penetrometer apparatus. Roughness was quantified using a modified Wheelchair Pathway Roughness Index at different locations along the treated rail surface and on the untreated surface. At each of the testing locations on the treated surface, stability was shown to have improved, firmness was relatively consistent, and the ability to roll an occupied wheelchair without rutting was markedly improved.]]></description>
      <pubDate>Tue, 13 Dec 2022 10:03:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2081510</guid>
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