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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>EFFECT OF PERCENT COMPACTION ON ASPHALT MIXTURE LIFE</title>
      <link>https://trid.trb.org/View/211853</link>
      <description><![CDATA[One of the major difficulties in asphalt concrete pavement construction is the control of materials and the subsequent level of payment to contractors for materials not conforming to specifications.  The effect of this noncompliance on pavement serviceability is not fully established; however, it frequently results in reduced payments to contractors, which, in turn, causes much controversy between the two parties.  Specific mixture properties outside specification tolerance, which are accepted by most agencies through reduced payment include percent compaction, asphalt content, and mix gradation.  The reduced payment used normally relies heavily on the experience and judgment of the agencies; therefore, there is often wide disparity in the pay adjustment factors used.  The paper summarizes currently available techniques for estimating the modulus and fatigue life of asphalt mixtures and shows how these, together with existing failure criteria for fatigue and permanent deformation may be used to estimate the effects of changes in compaction on pavement life.  Secondly, the results of extensive laboratory tests on asphalt mixtures from three projects in Oregon are reported.  Tests were performed to evaluate the effect of mix variations (including density) on mix properties (modulus, fatigue life, and resistance to permanent deformation).  Tests were run using both as-compacted and conditioned (vacuum saturated followed by freezing then heat soaking) specimens.  The test used throughout was the ASTM Repeated Load Diametral Test (D 4123-82) modified slightly such that fatigue life could be evaluated.  The results of the test program indicated that percent compaction (or void content) was the most significant factor affecting mix performance. An increase in void content is associated with a decrease in modulus, fatigue life, and resistance to permanent deformation.  The result of the study findings was the development of new asphalt concrete compaction specifications for the state of Oregon.  Not only does the Oregon Department of Transportation (DOT) now require a higher standard of compaction (91% of American Association of State Highway and Transportation Officials (AASHTO) T209 maximum specific gravity), but they have also spelled out clearly the penalties for not achieving density. (Author)]]></description>
      <pubDate>Thu, 30 Nov 2000 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/211853</guid>
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    <item>
      <title>RELATIONSHIP BETWEEN THE RHEOLOGICAL PROPERTIES OF ASPHALT AND THE RHEOLOGICAL PROPERTIES OF MIXTURES AND PAVEMENTS. ASPHALT RHEOLOGY: RELATIONSHIP TO MIXTURE. A SYMPOSIUM SPONSORED BY ASTM COMMITTEE D-4 ON ROAD AND PAVING MATERIALS, NASHVILLE, TENNESSEE, 11 DECEMBER 1985. ASTM SPECIAL TECHNICAL PUBLICATION 941</title>
      <link>https://trid.trb.org/View/282561</link>
      <description><![CDATA[The central tenet of this paper is that a proper level of bearing capacity is essential to good asphalt pavement performance.  Methods for designing pavements with increased bearing capacity and methods for measuring this property are recommended.  Since the bearing capacity of asphalt pavements is seldom determined, the fact is often overlooked that many pavement failures that are attributed to stripping, inferior asphalt quality, and inferior stone quality are actually structural failures due to inadequate bearing capacity.  Increased truck tire pressures menace many pavements which were designed to traditional standards but which have bearing capacities too low to cope with the higher stress.  The only practical way to save these pavements from premature failure is to lower the stresses or tire pressure on them during hot weather.  The complexity of the rheology of asphalt and asphalt pavements and the poor precision of test methods used to measure these properties require that the conditions of test be carefully matched to road conditions in order that the results be meaningful. The use of aggregate graded to a high volume concentration and with a top size two-thirds the thickness of the pavement dramatically increases bearing capacity.  Low-viscosity asphalt and air voids of less than 3% greatly increase the durability of asphalt pavements.]]></description>
      <pubDate>Fri, 30 Jun 2000 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/282561</guid>
    </item>
    <item>
      <title>USING PAVING ASPHALT RHEOLOGY TO IMPAIR OR IMPROVE ASPHALT PAVEMENT DESIGN AND PERFORMANCE. ASPHALT RHEOLOGY: RELATIONSHIP TO MIXTURE. A SYMPOSIUM SPONSORED BY ASTM COMMITTEE D-4 ON ROAD AND PAVING MATERIALS, NASHVILLE, TENNESSEE, 11 DECEMBER 1985. ASTM SPECIAL TECHNICAL PUBLICATION 941</title>
      <link>https://trid.trb.org/View/282562</link>
      <description><![CDATA[The particular rheological property of a paving asphalt considered in this paper is its temperatre susceptibility. Currently neither ASTM nor the American Association of State Highway and Transportation Officials (AASHTO) has a temperature susceptibility requirement in its specification for paving asphalts.  For this reason, at the present time paving asphalt temperature susceptibility is far more often used to impair pavement performance than to improve it. Paving asphalt temperature susceptibility is defined in the paper and a method for its measure is indicated.  The influence of paving asphalt temperature susceptibility on pavement design and performance in hot climates without frost, and in cold climates with frost, is described.  Using the freezing index, Deg. F (Deg. C) days, as the criterion for the minimum temperature at any paving site, a very simple method is illustrated for selecting the optimum paving asphalt or asphalts for surface, binder and base course layers.  A set of requirements for paving asphalt temperature susceptibility, which can be added to a paving asphalt specification, is proposed and discussed.  It is shown that by the addition of suitable polymers, the temperature susceptibilities of paving asphalts can be changed dramatically.  This development implies that what has been always an asphalt supplier's market could change to an asphalt user's market.]]></description>
      <pubDate>Thu, 30 Jun 1988 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/282562</guid>
    </item>
    <item>
      <title>HOW THE PLASTIC BEHAVIOR OF ASPHALT MIXTURES INFLUENCE PAVEMENT LIFE. ASPHALT RHEOLOGY: RELATIONSHIP TO MIXTURE. A SYMPOSIUM SPONSORED BY ASTM COMMITTEE D-4 ON ROAD AND PAVING MATERIALS, NASHVILLE, TENNESSEE, 11 DECEMBER 1985. ASTM SPECIAL TECHNICAL PUBLICATION 941</title>
      <link>https://trid.trb.org/View/282563</link>
      <description><![CDATA[It seems from the author's theoretical and applied research that uncertainties in pavement life prediction could be reduced by paying attention to the plastic behavior of its component materials.  By ensuring that the relationship between the plastic behavior of the asphaltic concrete relative to that of the underlying layers (relative plastic behavior) is adjusted to an appropriate value, pavement life will be maximized.  The sensitivity analysis reported in this paper gives an insight into the effect of relative plastic behavior on pavement life.  The sensitivity analysis makes extensive use of the mechano-lattice stress-strain analysis of elastoplastic-layered media since it is able to detect the buildup of residual stresses and strains.  These can have the effect of either increasing or decreasing pavement life.  It is therefore hoped that the highway engineer will be able to make use of this information to prolong pavement life.  This he could do by designing the plastic behavior of the asphaltic concrete in the light of existing plastic behavior of the base and subgrade. Alternately the plastic behavior of the base and or the subgrade could be modified in the light of the plastic behavior of the asphaltic concrete.  The plastic behavior of the asphaltic concrete may be controlled by modifying the rheological properties of the asphalt or of the asphaltic concrete mix.]]></description>
      <pubDate>Thu, 30 Jun 1988 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/282563</guid>
    </item>
    <item>
      <title>EFFECT OF RHEOLOGICAL PROPERTIES OF ASPHALTS ON PAVEMENT CRACKING. ASPHALT RHEOLOGY: RELATIONSHIP TO MIXTURE. A SYMPOSIUM SPONSORED BY ASTM COMMITTEE D-4 ON ROAD AND PAVING MATERIALS, NASHVILLE, TENNESSEE, 11 DECEMBER 1985. ASTM SPECIAL TECHNICAL PUBLICATION 941</title>
      <link>https://trid.trb.org/View/282564</link>
      <description><![CDATA[Both load and nonload-associated cracking of asphalt pavements are prevalent in Canada and the northern United States.  It is essential to identify the rheological properties of the asphalt binder responsible for this type of distress.  An asphalt durability research project began with the construction of six test pavements in Pennsylvania in September 1976 using AC-20 asphalt cements from different sources.  For seven years (1976 to 1984), periodical performance evaluations were carried out, and climatological data were gathered.  The rheological properties of original and aging asphalt binders were evaluated from periodic core samples.  The stiffness moduli of original and aged asphalt binders and asphaltic concrete were determined by two indirect methods (Heukelom and McLeod) at -23 Deg. C. (-10 Deg. F) to evaluate low-temperature nonload-associated transverse cracking.  Diametral creep measurements were made on pavement cores after seven years in service.  Creep moduli were determined over a convenient range of loading times up to 1000 s and in the 4 to -20 Deg. C (39.2 to -20 Deg. F.) temperature range.  The creep data for each asphalt were reduced to a master curve using the superposition method so that the stiffness modulus of the viscoelastic asphaltic concrete can be obtained at a desired temperature and time of loading.  Both indirect methods and direct measurements indicate that the stiffness modulus of the asphaltic concrete is a better indicator of the potential low temperature nonload-associated cracking.  Asphalt ductility values, determined at 15.6 Deg. C. (60 Deg. F.) after six years in service, seem to be consistent with the pavement performance.  Higher ductility values are associated with lower incidence of load-associated longitudinal cracking. Recommendations have been made to optimize the rheological properties of asphalt binders and asphaltic concrete to minimize the incidence of both load and nonload-associated cracking of asphalt pavements.]]></description>
      <pubDate>Thu, 30 Jun 1988 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/282564</guid>
    </item>
    <item>
      <title>BASIC RHEOLOGY AND RHEOLOGICAL CONCEPTS ESTABLISHED BY H. E. SCHWEYER. ASPHALT RHEOLOGY: RELATIONSHIP TO MIXTURE. A SYMPOSIUM SPONSORED BY ASTM COMMITTEE D-4 ON ROAD AND PAVING MATERIALS, NASHVILLE, TENNESSEE, 11 DECEMBER 1985. ASTM SPECIAL TECHNICAL PUBLICATION 941</title>
      <link>https://trid.trb.org/View/282565</link>
      <description><![CDATA[The flow properties of asphalts are usually characterized as Newtonian, pseudoplastic, dilatant, Bingham plastic, and thixotropic.  Asphalts always exhibit some degree of elasticiy.  Therefore, even asphalts with Newtonian flow properties cannot be truly classified as Newtonian materials.  In general, we can consider these flow categories to be a function of the shear susceptibility (complex flow) of the material.  Most paving grade asphalts will exhibit Newtonian-like (C = 1.0) flow properties at or near conventional mix temperatures.  At high shear rates the material may develop pronounced dilatant behavior (C > 1.0). However, at low temperature (< 25 Deg. C.) we often observe a greater degree of pseudoplastic (C < 1.0) behavior.  The use of a fixed or specified shear rate for computation of asphalt viscosities at lower temperatures is often misleading and may result in erroneous interpretation of test results.  The advantage of using constant power viscosity (n sub j) is discussed in conjunction with viscosity-temperature regression analyses for evaluation of temperature susceptibility.  This paper presents a thorough and concise overview of rheological types with emphasis on the need for rheological measurements throughout a range in temperature.  The presentation discusses measurement methods and relies heavily on procedures purported by H. E. Schweyer as being excellent for the characterization of paving and roofing asphalts.  The theoretical basis of the Schweyer constant stress rheometer is fully presented.  The operation of the rheometer and procedure for analysis of data are described and illustrated by an example.  The application of low-temperature viscosity test results using the Schweyer rheometer is also shown by an example.]]></description>
      <pubDate>Thu, 30 Jun 1988 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/282565</guid>
    </item>
    <item>
      <title>IMPROVED RHEOLOGICAL PROPERTIES OF POLYMER-MODIFIED ASPHALTS. ASPHALT RHEOLOGY: RELATIONSHIP TO MIXTURE. A SYMPOSIUM SPONSORED BY ASTM COMMITTEE D-4 ON ROAD AND PAVING MATERIALS, NASHVILLE, TENNESSEE, 11 DECEMBER 1985. ASTM SPECIAL TECHNICAL PUBLICATION 941</title>
      <link>https://trid.trb.org/View/282566</link>
      <description><![CDATA[Polymer modification dramatically changes the rheological properties and therefore the performance of asphalt cement. This study discusses conventional and new methods of specification testing for the polymeric elastic and tensile properties.  Five asphalts were tested before and after polymer modification for penetration, viscosity, low temperature ductility, pen-vis numbers (PVM), and aging indices.  Tensile strength, force ductility, toughness and tenacity, dropping ball, creep response, elastic recovery by ductilometer, torsional recovery, sliding plate rheometry, Dekker elastic recovery, and temperature susceptibility test methods are also examined.  It is concluded that current asphalt cement specifications should be supplemented with tests for tensile strength and elastic recovery if the relative performance properties of polymerized asphalt cements are to be compared.]]></description>
      <pubDate>Thu, 30 Jun 1988 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/282566</guid>
    </item>
    <item>
      <title>RHEOLGICAL PROPERTIES OF SULFUR ASPHALT BINDERS WITH FILLERS DETERMINED BY THE SLIDING PLATE RHEOMETER. ASPHALT RHEOLOGY: RELATIONSHIP TO MIXTURE. A SYMPOSIUM SPONSORED BY ASTM COMMITTEE D-4 ON ROAD AND PAVING MATERIALS, NASHVILLE, TENNESSEE, 11 DECEMBER 1985. ASTM SPECIAL TECHNICAL PUBLICATION 941</title>
      <link>https://trid.trb.org/View/282567</link>
      <description><![CDATA[Sulfur continues to be favored as a potential asphalt extender in road paving operations.  Over the past decade, developments in the field of sulfur/asphalts (S/A) have proceeded at a rapid pace, leading to products and technologies that are currently at the early commercialization stage.  In this study, the properties of selected S/A binders mixed with three commonly used mineral fillers (cement, hydrated lime, and crushed limestone fines) were determined using the sliding plate rheometer. Variables have included loading time, temperature, and S/A weight ratio.  The results indicate that sulfur has a much greater influence on measured properties such as viscosity and stiffness than mineral fillers alone.  S/A binders, with hydrated lime filler, have exhibited higher viscosity and stiffness than binders prepared with cement or limestone fines.  The rheometer data, coupled with photomicrographs, support the notion that the morphology of S/A binders with fillers is very different from that of S/A binders alone in terms of potential voids, sulfur recrystallization, and the size of crystal platelets.]]></description>
      <pubDate>Thu, 30 Jun 1988 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/282567</guid>
    </item>
    <item>
      <title>POLMER-MODIFIED ASPHALT PROPERTIES RELATED TO ASPHALT CONCRETE PERFORMANCE. ASPHALT RHEOLOGY: RELATIONSHIP TO MIXTURE. A SYMPOSIUM SPONSORED BY ASTM COMMITTEE D-4 ON ROAD AND PAVING MATERIALS, NASHVILLE, TENNESSEE, 11 DECEMBER 1985. ASTM SPECIAL TECHNICAL PUBLICATION 941</title>
      <link>https://trid.trb.org/View/282568</link>
      <description><![CDATA[Mechanical properties of asphalts containing styrenic block copolymers and properties of dense-graded asphalt concrete produced from these binders are presented.  Materials studied include unmodified AC-5 and AC-20 asphalts and AC-5 containing 3 and 6% styrenic block copolymers.  Dynamic rheology of the binders was studied as a function of temperatre and deformation rate.  Complex viscosity of the polymer-modified asphalts exhibits less temperature susceptibility than that of control asphalts from 0 Deg. C (32 Deg. F) to 93 Deg. C (200 Deg. F) and slightly higher temperature susceptibility above 93 Deg. C (200 Deg. F). The modified asphalts are viscoelastic throughout the pavement operating temperature range with a significant elastic component.  However, the unmodified asphalts are essentially nonelastic above 38 Deg. C (100 Deg. F). Increases in polymer content increase viscosity, ductility, toughness, tenacity, and elasticity of the materials tested. However, shear-thinning characteristics of the polymer-modified asphalts allow handling by familiar techniques at conventional temperatures.  Asphalt concrete was evaluated by resilient modulus and indirect tension over a range of temperatures.  Results indicate tensile modulus is lowered at low temperatures and raised at high temperatures by addition of the polymer.]]></description>
      <pubDate>Thu, 30 Jun 1988 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/282568</guid>
    </item>
    <item>
      <title>ASPHALT RHEOLOGY TO DEFINE THE PROPERTIES OF ASPHALT CONCRETE MIXTURES AND THE PERFORMANCE OF PAVEMENTS. ASPHALT RHEOLOGY: RELATIONSHIP TO MIXTURE. A SYMPOSIUM SPONSORED BY ASTM COMMITTEE D-4 ON ROAD AND PAVING MATERIALS, NASHVILLE, TENNESSEE, 11 DECEMBER 1985. ASTM SPECIAL TECHNICAL PUBLICATION 941</title>
      <link>https://trid.trb.org/View/282560</link>
      <description><![CDATA[The behavior of asphalt concrete paving mixtures at low temperatures is primarily dependent upon the rheological properties of the asphalt binder.  The Schweyer Constant Stress Rheometer was used to define the low-temperature rheological properties of asphalts recovered from laboratory-compacted mixtures and field cores.  Asphalt viscosity relationships with resilient modulus, mix viscosity, static modulus, stiffness, fractures strain, fracture energy, and fracture stress of the mix were established using dynamic, static, and constant stress indirect tension testing procedures.  Resilient moduli predicted from the viscosity of asphalts recovered from pavements were used in elastic layer analyses to define deflection and strain basins produced by Dynaflect or plate tests.  These deflection and strain basins compared favorably with those measured on a test pit pavement and on selected in-service pavements.  Relationships between asphalt viscosity and mix parameters are presented to illustrate the importance of asphalt viscosity and to suggest their potential use in the modeling of the thermal behavior of flexible pavements.  It is shown that there is no appreciable difference between resilient and status moduli when asphalt viscosity exceeds about 400 MPa.s.  The importance of shear susceptibility for both asphalt and mix viscosity determinations is discussed with recommendations for use of constant power viscosity to minimize errors induced by extrapolation of viscosity at shear rates outside those obtained in the test.  Parameters for thermal and load induced fracture include stress, strain, and energy. Laboratory test results were used to develop relationships between these parameters and the constant power viscosity of the asphalt binder.  Tests on pavement cores produced fracture corresponding to that obtained in the laboratory tests.  Comments are provided on the reliability of these parameters in defining fracture.]]></description>
      <pubDate>Thu, 30 Jun 1988 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/282560</guid>
    </item>
    <item>
      <title>THIN SLURRY CUTOFF WALLS INSTALLED BY THE VIBRATED BEAM METHOD</title>
      <link>https://trid.trb.org/View/278096</link>
      <description><![CDATA[In recent years, thin slurry walls installed by vibrating a beam into the ground and injecting a suitable slurry as it is withdrawn have been used successfully and economically in a variety of applications, most notably as (a) permanent seepage cutoffs either in new or existing dams or levees, (b) a means of temporarily controlling groundwater during construction, and (c) a device for containment of toxic wastes.  This paper describes the equipment and construction techniques for installing the cutoff, and details of various types of slurries for different applications are given.  The results of field investigations undertaken to assess the permeability and continuity of vertical and battered (inclined) slurry walls are presented.  (Author/TRRL)]]></description>
      <pubDate>Sun, 31 Jan 1988 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/278096</guid>
    </item>
    <item>
      <title>OPPORTUNITIES WITH ALKALIES IN CONCRETE TESTING, RESEARCH, AND ENGINEERING PRACTICE</title>
      <link>https://trid.trb.org/View/284452</link>
      <description><![CDATA[From about 1940 alkalies have been known as a potentially important species in concrete, despite being a minor cement constituent.  The hydration reaction of silica in aggregates in concrete in the presence of alkalies, which may cause deleterious expansion, is chemically similar to the process which makes finely ground cementitious components, such as blast-furnace slag, and mineral admixtures, such as fly ashes, natural pozzolana, and silica fume, able to prevent expansive reactions.  The chemistry of this process is briefly reviewed, and the impact of elevated temperatures, which occur more in field concrete than in laboratory concrete and mortars, is discussed.  The adventageous effects of alkalies on the rheology of concrete containing mineral admixtures are discussed with reference to recent research regarding the electrochemistry of cement paste. The corresponding effect in densifying the microstructure of the cement paste in hardened concrete is also discussed. Updating of the application of silicate chemistry is proposed as a basis for development of testing tailored to serve effectively the increased uses of the mineral admixtures.]]></description>
      <pubDate>Wed, 30 Sep 1987 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/284452</guid>
    </item>
    <item>
      <title>ALKALI-SILICA REACTIVITY: EFFECT OF ALKALI IN AGGREGATE ON EXPANSION</title>
      <link>https://trid.trb.org/View/284453</link>
      <description><![CDATA[Tests were performed on samples of alkali-bearing aggregates to determine amounts of alkali that could be removed by leaching in Ca(OH)2 solution and water at 38 deg. C (100 deg. F) and 80 deg. C (176 deg. F).  Additional tests were made on one reactive aggregate which was first subjected to leaching and then used to make mortar bars for testing in accordance with ASTM C 227.  Leach periods of 7, 28, 90, and 180 days were used.  Results show that alkali present within concrete aggregate particles may participate in alkali-silica reactivity.  Alkali levels much greater than these present in high-alkali cements can be leached from non-reactive as well as reactive aggregate materials.  It is suggested that ion-exchange processes possibly augmented by partial dissolution of the aggregate, facilitate leaching of alkali.  Removal of alkali from aggregates, prior to their use in mortar bars, was shown to reduce expansions. Expansions were progressively reduced as greater amounts of alkali were leached from aggregates prior to their use with low- as well as high-alkali cements.  Applicability of these findings to concrete in service is discussed.]]></description>
      <pubDate>Wed, 30 Sep 1987 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/284453</guid>
    </item>
    <item>
      <title>INFLUENCE OF CEMENT ALKALI DISTRIBUTION ON EXPANSION DUE TO ALKALI-SILICA REACTION</title>
      <link>https://trid.trb.org/View/284454</link>
      <description><![CDATA[In order to better understand the factors controlling alkali-silica reaction, a study was carried out to show if the distribution of alkalies among the cement minerals influences the expansion of mortar containing reactive aggregate.  The approach was to determine the distribution of alkalies in four high-alkali portland cements, and to measure expansion of mortar bars prepared using these cements and reactive aggregates.  In some cases, differences were observed in both the ultimate level and the early rate of expansion for cements differing in distribution of alkalies.  The differences were substantial with opals as the reactive constitutent.  Cements richer in soluble alkali-sulfate phases appeared to show greater levels and rates of expansion.  The results demonstrate that the specific distribution of alkalies among the cement minerals affects the expansion due to alkali-silica reaction.]]></description>
      <pubDate>Wed, 30 Sep 1987 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/284454</guid>
    </item>
    <item>
      <title>CORRELATING WATER-SOLUBLE ALKALIES TO TOTAL ALKALIES IN CEMENT - CONSIDERATIONS FOR PREVENTING ALKALI-SILICA POPOUTS ON SLABS</title>
      <link>https://trid.trb.org/View/284455</link>
      <description><![CDATA[This paper reviews the problem of alkali-silica surface popouts on slabs in the north central United States and adjacent southern Canada.  Based on the review, it is concluded that the popouts occur as a result of reaction of alkalies in the concrete with siliceous shale in the concrete sand.  The reaction is caused by increased alkali concentration at the slab surface, which results when soluble alkalies are left behind by evaporating mixing water.  The soluble alkalies in the cement, fly ash, aggregates, admixtures, and mixing water contribute to alkalies in solution.  Weather conditions and placing and finshing methods are primarily responsible for concentration of water-soluble alkalies at the slab surface where the popouts occur.  The correlation between water-soluble alkalies and total alkalies is determined for a plant which produces cement that has several levels of alkali.  The results indicate good correlation, but the benefit of reduction of total alkalies on resultant level of water-soluble alkalies does not appear significant compared to other factors which cause greatly increased alkali concentation at the slab surface.  Cements from other sources are also compared for correlation.  The results indicate the portion of the total alkalies which is water-soluble varies widely from one cement plant to another and within the production from some plants.]]></description>
      <pubDate>Wed, 30 Sep 1987 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/284455</guid>
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