<rss version="2.0" xmlns:atom="https://www.w3.org/2005/Atom">
  <channel>
    <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" />
    <description></description>
    <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>
    </image>
    <item>
      <title>Cement-treated crushed stones: influence of cement type on mixture porosity</title>
      <link>https://trid.trb.org/View/2598416</link>
      <description><![CDATA[The study analysed the absorption and void content of CTCS mixtures with two cement types (CP II-F 32 and CP IV 32 RS) and binder levels (3% and 5%) to evaluate the impact of cement type on porosity. The results indicated that replacing CP II-F 32 cement with CP IV 32 RS cement leads to mixtures that are less porous, more compact, and with stronger bonds between mortar and aggregate. The macro and microstructure images corroborated the results obtained. Complementary analyses of the mechanical behavior of the mixtures showed that mixtures with CP IV had higher strengths and stiffnesses compared to mixtures with the same CP II cement content, indicating a better performance of mixtures with cement containing a high content of pozzolanic material. Factorial models highlighted a strong correlation between porosity and mechanical properties, demonstrating that reduced absorption and void indices result in higher performance.]]></description>
      <pubDate>Mon, 24 Nov 2025 15:30:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2598416</guid>
    </item>
    <item>
      <title>Effect of High Temperatures on the Behavior of Self-Compacting Mortar Containing Calcined Mud and Natural Pozzolan</title>
      <link>https://trid.trb.org/View/2606670</link>
      <description><![CDATA[This study investigates the behavior of self-compacting mortar (SCM) containing calcined mud (CM) from dam and natural pozzolan (NP) subjected to high temperatures. Ten formulations were tested: one control and nine incorporating binary and ternary systems of Portland cement, CM, and NP, with substitution rates of 10%, 20%, and 30%. The compressive was evaluated at 7, 28, 90, and 180?days. SCM specimens were exposed to three high temperatures (400°C, 600°C, and 800°C) for 2?h. Fresh properties of SCM were assessed using mini-slump and mini-V funnel tests. Results showed a reduction in superplasticizer demand for SCMs containing CM and NP. Before and after high-temperature exposure, the binary mix containing 10% of CM and the ternary mix with 5% of CM and 5% of NP showed superior compressive strength.]]></description>
      <pubDate>Tue, 07 Oct 2025 09:12:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/2606670</guid>
    </item>
    <item>
      <title>State of Practice of Pozzolanic Concrete in Infrastructure Projects



</title>
      <link>https://trid.trb.org/View/2600544</link>
      <description><![CDATA[With the understanding of the advancements in the use of pozzolanic concrete to reduce carbon dioxide emissions, the Senate Committee on Environment and Public Works has requested reports on the use of low-carbon materials, including pozzolanic concrete, in federally funded projects. The request noted that the report should include steps taken to assess the durability, strength, cost, and environmental impacts of pozzolanic concrete compared with existing concrete products. The U.S. Department of Transportation Office of the Assistant Secretary for Research and Technology (US DOT OST-R), in coordination with the Federal Highway Administration (FHWA), will submit to the Committee a report on the use of pozzolanic concrete in federally funded infrastructure projects. The US DOT OST-R requested the TRB Cooperative Research Programs (CRP) to facilitate the conduct of this work and the preparation of the requested report. Research is needed to document the use of pozzolanic materials in concrete used in infrastructure projects and prepare the requested report.

The objective of this project is to document the use of pozzolanic materials in concrete used in infrastructure projects and prepare reports on the state of practice of pozzolanic concrete in infrastructure projects and in federally funded infrastructure projects. The latter report shall be prepared in a format appropriate for submission to the U.S. Congress. The research shall consider the use of fly ash, silica fume, and other pozzolans, both singularly and in combination. The documentation shall include the criteria and methods used to assess suitability of these materials for use in concrete structures, e.g., concrete properties such as durability and strength, estimated service life, economic considerations, and environmental impacts. For this project, pozzolanic concrete is defined as concrete containing pozzolanic materials. The research shall consider FHWA funded projects, projects located on federal lands, and projects using the formula and discretionary grants funds.]]></description>
      <pubDate>Thu, 18 Sep 2025 16:08:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2600544</guid>
    </item>
    <item>
      <title>Aggregate Alkali-Silica-Reactivity and Mitigative Measures</title>
      <link>https://trid.trb.org/View/2582928</link>
      <description><![CDATA[Alkali-Silica-Reactivity (ASR) is a well-documented issue with aggregate used in concrete throughout New Mexico. Historically, inexpensive coal fly ash (FA), a waste byproduct of power generation with pozzolanic properties, has been relied on as an effective means of mitigating ASR. As more and more coal-fired power plants are retired and replaced by natural gas power plants and renewable energy sources, FA is no longer a reliable and readily available source of material for mitigating ASR. Natural pozzolans currently used for ASR mitigation, such as pumicite and metakaolin, are available but are costly. New Mexico has many undeveloped sources of alternative natural pozzolans which could be utilized with proper characterization and become a significant economic contribute to the state’s economy. Establishing a statewide alkali-aggregate reaction (AAR) database based on detailed ASR testing is required to provide high quality concrete with excellent long-term performance necessary for the construction of highly safe and durable concrete transportation structures. It is expected future changes to concrete specifications will reduce supply burdens and costs for quality concrete, while at the establishing local sources for alternative pozzolans, benefiting local economies, as well as concrete suppliers and customers.]]></description>
      <pubDate>Tue, 05 Aug 2025 13:32:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2582928</guid>
    </item>
    <item>
      <title>Development of a Type IP Cement, Supplementary Report 3: Effect of Natural Pozzolans and Fly Ash on Alkali-Silica Reactivity</title>
      <link>https://trid.trb.org/View/2556750</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 IP 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 ASTM 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 in the Black Hills area. 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. The effectiveness of pozzolans in controlling the ASR expansion depended on the type, moisture content, quality, and quantity of pozzolan blended with cement. Calcining the pozzolans has improved the strength activity index.]]></description>
      <pubDate>Mon, 07 Jul 2025 21:59:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/2556750</guid>
    </item>
    <item>
      <title>Demonstration of Pozzolan Modified Cement to Mitigate ASR</title>
      <link>https://trid.trb.org/View/2522020</link>
      <description><![CDATA[In 1991, the South Dakota Department of Transportation (SDDOT) commissioned a research study to determine the feasibility of producing a cement that would not induce alkali-silica reactivity (ASR). The South Dakota School of Mines and Technology (SDSM&T), under contract to SDDOT, successfully identified suitable deposits of natural pozzolans near Rapid City, SD and demonstrated that ASR could be stopped by incorporating the material in cement. Since the research completed in 1994, Dacotah Cement, a cement manufacturer in Rapid City, SD, has produced trial quantities of pozzolan modified cement. Based on laboratory test results, the cement - designated Type IPM - shows potential to prevent concrete deterioration from ASR. Because the pozzolan does not require calcining before intergrinding, the modified cement is economical. Strength and durability testing was completed to verify the cement's usefulness in widespread use. Through the testing involved in this project, it has been shown that concrete made with Dacotah Type IPM cement has compressive and flexural strengths approximately 10 - 12% lower than standard Type I/II cement mixtures. This is probably due to the fact that 10% of the cement is replaced with a natural pozzolan. Cores taken from field test sections showed compressive strengths 20 to 40% lower than strengths of laboratory concrete specimens. Time of set for the Type IPM cement is lower than that of Type I/II, mainly due to Type IPM cement being finer than Type I/II. Freeze/thaw and deicer scaling durability of this new cement is equal to the standard Type I/II used as a control.]]></description>
      <pubDate>Mon, 24 Mar 2025 18:13:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2522020</guid>
    </item>
    <item>
      <title>Mitigation of Potential Alkali-Silica Reactivity Using Lithium (SHRP Concrete and Structures ASR Showcase Test and Evaluation Project 34)</title>
      <link>https://trid.trb.org/View/2522016</link>
      <description><![CDATA[This research involved participation in an FHWA-sponsored round robin testing program using the AASHTO TP-14 procedure for accelerated testing of Alkali-Silica Reactive (ASR) aggregates. In addition, thirteen Portland cement concrete pavement test sections were constructed incorporating fly ash, lithium compounds and pozzolan modified cement as mitigation techniques. These test sections will be monitored for four more years to gauge the effectiveness of the various treatments using static modulus testing and comparing all results against a control section with no treatment. Several of the treatment protocols involved the use of a combination of an F fly ash with different addition levels of lithium admixtures which constitutes the most potentially economical method for mitigation using lithium compounds. Six test sections using various amounts of neutral lithium compounds on an existing pavement suffering from severe ASR distress were also established by spraying solutions onto the slab. Initial results, based on static modulus values before and after treatment, are encouraging but further data must be collected before conclusive evidence of a positive benefit.]]></description>
      <pubDate>Mon, 24 Mar 2025 18:13:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2522016</guid>
    </item>
    <item>
      <title>Development of a Type IP Cement Supplementary Report 4: Physical and Elastic Properties of Natural PozzoIan Blended (Type-lP) Cement Concretes</title>
      <link>https://trid.trb.org/View/2519068</link>
      <description><![CDATA[Alkali reactive sands or coarse aggregates, when used in concrete structures, produce severe deterioration because of expansion and cracking. The use of pozzolan blended cement is an attractive solution to mitigate this problem. This represents the results of an experimental investigation to evaluate the characteristics of pozzolan blended cement concretes. A comparison of these properties with those of unblended cements is also given. The Type I/II cement was blended with three different amounts of 10%, 15%, 25% by weight of cement with five different types of natural pozzolans available in the western South Dakota near Rapid City. The tests carried out include: (1) Fresh concrete properties such as slump, unit weight, vebe time, air content. and concrete temperature and (2) Hardened concrete properties such as compressive strength, static modulus of elasticity, flexural and impact strengths. All tests were done according to the ASTM recommendations and procedures. Good workability of concrete was achieved even though the water content was kept uniformly the same for all mixes, without adding any water reducing agent or superplasticizer. The test results indicated that there was no significant difference in the physical properties of pozzolan blended cement concretes in comparison with control concrete during mixing and placing. An increase in the pozzolan content slightly decreased the compressive strength and modulus of rupture. The static modulus results indicated that the values were almost the same for all the concretes. From the results of the static flexure test, load deflection curves were plotted from which the toughness indexes were calculated according to the ASTM standard method. The toughness indexes (ASTM) decreased slightly with an increase in the amount of pozzolan.]]></description>
      <pubDate>Mon, 24 Mar 2025 12:27:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2519068</guid>
    </item>
    <item>
      <title>Development of a Type IP Cement Supplementary Report 2: A Comparative Study of the Physical Properties of Six Natural Pozzolan Blended Type-IP Cements</title>
      <link>https://trid.trb.org/View/2519069</link>
      <description><![CDATA[Cement contains many ingredients of which alkalies are minor compounds. Alkali reactive sands or coarse aggregates when used in concrete structures cause a major problem due to cracks formed by the expansive reaction between alkalies in cement and reactive forms of silica in aggregates. Use of natural pozzolans as a cement replacement is effective in inhibiting expansive alkali-silica reactivity. This investigation presents the experimental results to evaluate the physical properties of six natural pozzolans blended Type-IP cement specimens with 10, 15, and 25 percentages of pozzolans. The tests carried out include: 1. Physical properties of cement mortar such as compressive strength by ASTM C109 and air content by ASTM C185; 2. Physical properties of cement paste such as normal consistency by ASTM C187, time of setting by ASTM C191 and ASTM C266, and early stiffening of cement paste by ASTM C451; and 3. Physical properties of cement such as fineness by ASTM C430 and ASTM C204, and density by ASTM C188. From the test results it can be stated that there is no significant difference in the physical properties of cement mortar, cement paste, and cement, blended with 10 percent of LK2 natural pozzolan, when compared to respective properties of plain Portland cement mortar, cement paste, and cement.]]></description>
      <pubDate>Mon, 24 Mar 2025 12:27:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2519069</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>Micro aggregate and pozzolanic reactivity of fly ash: effect on fracture properties</title>
      <link>https://trid.trb.org/View/2475175</link>
      <description><![CDATA[]]></description>
      <pubDate>Tue, 10 Dec 2024 10:07:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2475175</guid>
    </item>
    <item>
      <title>Effect of magnetic water on properties of structural lightweight expanded polystyrene concrete</title>
      <link>https://trid.trb.org/View/2389460</link>
      <description><![CDATA[]]></description>
      <pubDate>Wed, 12 Jun 2024 09:25:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2389460</guid>
    </item>
    <item>
      <title>Pozzolanic Reactivity of High-Alkali Supplementary Cementitious Materials and Its Impact on Mitigation of Alkali-Silica Reaction</title>
      <link>https://trid.trb.org/View/2382100</link>
      <description><![CDATA[The growing scarcity of conventional supplementary cementitious materials (SCMs) such as Class F, Class C fly ashes, and slag has necessitated exploring alternative SCMs previously considered suboptimal. In particular, high-alkali SCMs are often avoided because of the potential concern that their alkali content could release into the concrete pore solution, thus exacerbating the potential for alkali-silica reaction (ASR). However, preliminary research indicates that not all high-alkali SCMs are deleterious, and some can effectively suppress the ASR expansive reaction when used in sufficient dosage levels. This study evaluates the feasibility of using high-alkali SCMs, such as high-alkali natural pozzolans and reclaimed fly ashes, focusing on their pozzolanic reactivity and the correlation between the reactivity and their ASR mitigation performance. The pozzolanic reactivity of the SCMs was evaluated by the R3 test per ASTM C1897 and strength activity index test per ASTM C311. Thermogravimetric analysis was used to determine the calcium hydroxide consumption by the SCMs. ASR mitigation performance of SCMs was evaluated in accordance with American Association of State Highway and Transportation Officials (AASHTO) T380 miniature concrete prism test. Additionally, pore solution expression and analysis of paste specimens were conducted to determine the correlation between the total alkali and the released alkali levels into the pore solution. Based on the results of this study, all SCMs indicated high pozzolanic reactivity; however, individual performance varied by test method. Ultimately, the high-alkali SCMs, particularly natural pozzolans, did not appear to release any significant levels of alkalis into the pore solution readily and, therefore, show potential for ASR mitigation when used in sufficient dosage levels.]]></description>
      <pubDate>Mon, 27 May 2024 10:10:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/2382100</guid>
    </item>
  </channel>
</rss>