<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>Multi-Electrode Conductivity Method to Evaluate Static Stability of Flowable and Self-Consolidating Concrete</title>
      <link>https://trid.trb.org/View/814634</link>
      <description><![CDATA[In cement-based materials, coarse aggregate segregation can lead to heterogeneity in hardened material properties with direct mechanical properties and durability implications. Segregation control is especially critical in self-consolidating concrete (SCC) and flowing concrete, as well as in concrete made with fillers used for partial cement replacement or supplementary cementitious materials. The authors attempted to develop a rapid segregation estimation methodology during the dormant cement hydration period, monitoring changes through electrical conductivity in local composition over specimen height, as a time function. Multi-pair electrode conductivity method results were compared with those obtained through actual segregation study determined on hardened concrete samples through an image processing technique of tracing and counting, along hardened cylindrical sections, aggregate particles. In total, testing was done on 5 SCC mixtures with a slump flow value range of 650 and 880 mm (excessive) (25.6 to 34.7 inches) and 9 concrete mixtures with a slump value range of 70 to 240 mm (2.76 to 9.45 inches). A high correlation degree was established between electrical conductivity results and image analysis methods. Electrical conductivity data obtained after 20 minutes of testing are shown to correlate well with homogeneity, segregation and bleeding indexes determined from, at typically greater than 3 hours peak conductivity, an electrical conductivity approach, as well as an image analysis-determined segregation index. Static stability following concrete placement evaluation can be done nondestructively through the conductivity approach.]]></description>
      <pubDate>Thu, 23 Aug 2007 13:00:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/814634</guid>
    </item>
    <item>
      <title>Getting it Right: Successful SCC Production Practices</title>
      <link>https://trid.trb.org/View/811077</link>
      <description><![CDATA[This paper describes how the challenge of producing successful self-consolidating concrete (SCC) is based on consistently achieving high flow and high stability. The foundation of high quality SCC production is the suitability of the underlying materials and a mixture design that is optimized for those materials and the application. Not all applications require relatively high slump flows in the range of 28-30 inches (700- 750mm), where control measures need to be especially well managed. Furthermore, even the best mixture designs can have stability limitations. In order to assure that SCC applications proceed with minimal difficulties, the concrete producer must anticipate variations in materials and production operations by using effective quality control procedures. Changes in cement reactivity, aggregate properties (gradation, shape, and water demand), free moisture, and extra sources of moisture that may be present, for instance, in the truck, and the mixing process need to be carefully monitored. This paper will discuss specific examples that demonstrate best practices in mixture design, QA/QC, and production techniques.]]></description>
      <pubDate>Fri, 22 Jun 2007 09:17:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/811077</guid>
    </item>
    <item>
      <title>A New, Portable Rheometer for Fresh Self-Consolidating Concrete</title>
      <link>https://trid.trb.org/View/811088</link>
      <description><![CDATA[This paper describes how the accurate determination of fresh concrete rheology is key in ensuring the production of self-consolidating concrete (SCC) is successful. However, rheometers are used infrequently in the field and empirical test methods are most commonly used to determine SCC workability despite measuring quantities that are related to rheological parameters only in an indirect way, if at all. Instead of using multiple empirical test methods to measure the workability of SCC, it is desirable to use a rheometer in both the laboratory and field to determine the flow properties of SCC quickly. Existing rheometers are generally unsuitable for routine field use because of their large size, high cost, or both. This paper describes the use of the International Center for Aggregates Research (ICAR) rheometer, a low-cost, fully portable device that can measure concrete mixtures ranging in workability from approximately 50 mm in slump to SCC. Laboratory test results of SCC mixtures and field testing experience are presented to demonstrate the validity and practicality of the ICAR rheometer.]]></description>
      <pubDate>Fri, 22 Jun 2007 09:17:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/811088</guid>
    </item>
    <item>
      <title>Coarse Aggregate and Self-Consolidating Concrete Passing Ability</title>
      <link>https://trid.trb.org/View/811087</link>
      <description><![CDATA[This paper examines the effect of aggregate content and gradation on self consolidating concrete (SCC) passing ability. Passing ability is defined as an SCC mixture’s ability to flow through narrow spaces without segregating or blocking. The mixtures tested ranged over two uniform aggregate sizes, two aggregate contents, two different mixture design philosophies, and a gradated aggregate mixture. Passing ability tests, slump flow tests, horizontal flow tests, and stereology tests were performed on these mixtures. Stereology is a statistical counting technique used primarily by natural scientists and concrete researchers have used sterolog to describe bubble size and distribution in concrete. A vertical flow box was developed by McBride to determine the passing ability of the various mixtures. Various bar spacings are tested. From the results of this study, it seems that two stereology parameters can be correlated to the minimum bar spacing that will allow SCC to pass. These parameters are the ratio of maximum aggregate size to mean aggregate free distance and the ratio of maximum aggregate size to mean aggregate random spacing.]]></description>
      <pubDate>Fri, 22 Jun 2007 09:17:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/811087</guid>
    </item>
    <item>
      <title>Effect of Various Admixture-Binder Combinations on Workability of Ready-Mix Self-Consolidating Concrete</title>
      <link>https://trid.trb.org/View/811083</link>
      <description><![CDATA[This paper describes an experimental investigation that was carried out in order to evaluate the effects of high range water reducing admixture (HRWRA), viscosity-enhancing admixture (VEA), and binder type on key workability characteristics of self-consolidating concrete (SCC), including retention of deformability, passing ability, and stability. Concrete-equivalent mortar (CEM) mixtures were prepared to evaluate the effect of admixture-binder combinations on flow characteristics, including minimum water content (MWC) to initiate flow and relative water demand (RWD) to increase a given fluidity. Four polycarboxylate-based HRWRAs, a  polynaphthalene sulfonate-based HRWRA, four types of VEAs, and three blended cements were evaluated. In total, 16 SCC mixtures with initial slump flow consistency of 660 +/- 20 mm and air volume of 6.5 +/- 1.5%, and 17 CEM mixtures were investigated. Flow characteristics of SCC and CEM mixtures made with a number of admixture-binder combinations indicate that the efficiency of admixture-binder combination depends on water-to-cementitious material ratio (w/cm), type of binder, and type of admixtures. The CEM approach can be used to evaluate the effect of admixture-binder combination on flow characteristics because the increase in MWC to initiate flow of CEM corresponds to higher demand in HRWRA in SCC mixtures. Binder type was shown to have marked influence on the retention of slump flow, L-box and V-funnel passing ability, filling capacity, and surface settlement characteristics. The binder type also affects HRWRA and air-entraining admixture (AEA) demand. As established from CEMs, B3 quaternary cement with the smallest 50% passing diameter had the highest MWC (lowest packing density) needed to initiate flow and the highest RWD (highest robustness to changes in water). SCCs made with such quaternary cement and polycarboxylate-based HRWRA also exhibited the highest HRWRA demand compared those prepared with other blended cements. Both sets of SCCs made with 0.35 w/cm and 0.42 w/cm plus VEA had similar HRWRA demand and static stability when the polycarboxylate-based HRWRA was used.]]></description>
      <pubDate>Fri, 22 Jun 2007 09:17:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/811083</guid>
    </item>
    <item>
      <title>LOW-HEAT DEVELOPMENT IN FLOWING CONCRETES FOR MASSIVE STRUCTURES</title>
      <link>https://trid.trb.org/View/664139</link>
      <description><![CDATA[The aim of this paper was to research production of crack-free massive concrete structures by use of flowing mixtures characterized by low heat development and certain mixture formulation performances; namely, compressive strength of 30-40 MPa at 28-90 days, and slump level of about 200 mm. Primary mixture ingredients were: normal portland cement; fly ash as pozzolanic mineral addition; ground limestone as filler; superplasticizers based on acrylic or sulfonated napthalene polymers; and natural aggregates with maximum size of 20 mm.]]></description>
      <pubDate>Wed, 24 Sep 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/664139</guid>
    </item>
  </channel>
</rss>