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    <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" />
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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>
    <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>EXPANSIVE CONCRETES - LABORATORY TESTS OF FREEZE-THAW AND SURFACE SCALING RESISTANCE</title>
      <link>https://trid.trb.org/View/95480</link>
      <description><![CDATA[TO STUDY THE FREEZE-THAW AND SURFACE SCALING RESISTANCE OF SELF-STRESSING AND SHRINKAGE-COMPENSATING CONCRETES, 112 SLAB SPECIMENS, 3X6X15 IN., WERE CAST AND SUBJECTED TO LABORATORY TESTS. FIVE DIFFERENT CEMENTS WERE INCLUDED IN THE STUDY' A PORTLAND CEMENT, TWO MIXTURES OF PORTLAND CEMENT AND PULVERIZED ANHYDROUS CALIUM SULFOALUMINATE CLINKER /KLEIN EXPANSIVE COMPONENT/ DESIGNATED S AND K, AND TWO BLENDS OF PORTLAND CEMENT, CALCIUM ALUMINATE CEMENT, AND GYPSUM- DESIGNATED B-1 AND B-2. MIXES S AND B-1 WERE CONSIDERED TO BE SHRINKAGE-COMPENSATING, AND MIXES K AND B-2 SELF-STRESSING. INTERNAL RESTRAINT WAS PROVIDED BY THREE REINFORCING SCHEMES, USING WELDED-WIRE FABRIC. SOME SPECIMENS WERE UNREINFORCED. TWO METHODS OF CURING WERE INCLUDED. ALL CONCRETES CONTAINED ABOUT 8 BAGS OF CEMENT /INCLUDING EXPANSIVE MATERIALS/ PER CUBIC YARD, AND ENTRAINED AIR. STRESSES DEVELOPED RANGED UP TO ABOUT 600 PSI IN THE SELF-STRESSING CONCRETES, AND UP TO ABOUT 120 PSI IN THE SHRINKAGE-COMPENSATING CONCRETES. THE SHRINKAGE- COMPENSATING CONCRETES WERE SUBJECTED TO 300 CYCLES OF FREEZING AND THAWING IN WATER OR 300 CYCLES OF DE-ICER APPLICATION WITHOUT SIGNIFICANT DETERIORATION. THE SELF- STRESSING CONCRETES REQUIRED CONSIDERABLE REINFORCEMENT RESTRAINT TO WITHSTAND 300 FREEZE-THAW CYCLES, NONE OF THE SELF-STRESSING CONCRETE SPECIMENS SURVIVED 300 CYCLES OF DE-ICER APPLICATION. /AUTHOR/]]></description>
      <pubDate>Thu, 05 Jun 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/95480</guid>
    </item>
    <item>
      <title>ANHYDROUS MINERALS AND ORGANIC MATERIALS AS SOURCES OF DISTRESS IN CONCRETE</title>
      <link>https://trid.trb.org/View/101390</link>
      <description><![CDATA[THE PURPOSE OF THIS REPORT IS TO DEFINE THE EXTENT OF THE PROBLEMS THAT EXIST WITH RESPECT TO THE DETERIORATION OF CONCRETE FROM REACTIONS INVOLVING /A/ HYDRATION OF PARTIALLY OR COMPLETELY DEHYDRATED COMPONENTS OF THE AGGREGATE, AND /B/ REACTIONS OF ORGANIC MATERIALS ASSOCIATED WITH AGGREGATES. THE FIRST PART OF THIS ASSIGNMENT IS TO THEORIZE AS TO WHAT COMPOUNDS COULD EXIST IN EITHER NATURAL OR ARTIFICIAL AGGREGATES IN FORMS IN WHICH THEY MIGHT CAUSE DISTRESS IN CONCRETE BY COMBINING WITH WATER. THIS APPROACH APPLIES ALSO TO WHAT MIGHT BE CLASSED BY-PRODUCT AGGREGATES SUCH AS CINDERS AND SLAGS. /AUTHOR/]]></description>
      <pubDate>Mon, 12 Dec 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/101390</guid>
    </item>
    <item>
      <title>SULFATE-BEARING PHASES IN STEAM-CURED CEMENT PASTES</title>
      <link>https://trid.trb.org/View/96155</link>
      <description><![CDATA[CEMENT AND CEMENT-POZZOLAN PASTES CONTAINING ADDED GYPSUM ABOVE CERTAIN AMOUNTS, AND CURED AT TEMPERATURES ABOVE 120 DEGREES C., CONTAINED BOTH ANHYDRITE AND A SULFATE-BEARING APATITE MINERAL, ELLESTADITE. HYDROGARNET, WHEN PRESENT, MIGHT ALSO OCCUR IN A SULFATE-SUBSTITUTED FORM AS SUGGESTED BY VARIATION IN UNIT CELL DIMENSIONS. THE THIN SURFACE DEPOSIT ON TYPE I CEMENT PASTE EXPOSED TO CONCENTRATED SEA WATER AT 121 DEGREES CONTAINED MAGNESIUM HYDROXY SULFATE HYDRATE AS A MAJOR PRODUCT. TOBERMITE (11A) CONTAINED LATTICE SUBSTITUTED SULFATE, WHICH AMOUNTED TO 1.6% IN REFERENCE SPECIMENS PREPARED AT 175 DEGREES C. ETTRINGITE OR "MONOSULFATE" WAS NOT DETECTED.]]></description>
      <pubDate>Thu, 24 Nov 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/96155</guid>
    </item>
    <item>
      <title>WORKS CARRIED OUT IN ANHYDRITE AND GYPSUM DEPOSITS /SPANISH/</title>
      <link>https://trid.trb.org/View/99463</link>
      <description><![CDATA[THE PAPER DESCRIBES THE CONDITIONS UNDER WHICH THE HEADWATER TUNNELS FOR TWO HYDROELECTRIC PLANTS IN ALGERIA WERE CONSTRUCTED THROUGH EXTENSIVE GYPSUM AND ANHYDRITE DEPOSITS. THE RENFORCEMENT OF THE TUNNEL WALLS WITH AN EXTRA LAYER OF CONCRETE IS DESCRIBED TOGETHER WITH THEIR WATERPROOFING; A HIGH-QUALITY CALCIUM SULPHATE RESISTANT CEMENT WAS USED. DETAILS ARE GIVEN OF SOM LABORATORY TESTS ON THE TRANSFORMATION OF ANHYDRID INTO GYPSUM. THE CALCULATION OF TUNNEL SURFACINGS IN SOIL BONTAINING SULPHATE IS BASED ON THE RESULTS OF THOSE TESTS. /LCPC/RRL/]]></description>
      <pubDate>Thu, 24 Nov 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/99463</guid>
    </item>
    <item>
      <title>OPTICAL MICROSCOPY OF CEMENT SILICATES</title>
      <link>https://trid.trb.org/View/98531</link>
      <description><![CDATA[USED BY CERILH TO CONTROL THE MANUFACTURE OF CLINKER AND TO STUDY THE HYDRATION OF CEMENT, OPTICAL MICROSCOPY GIVES INFORMATION ON THE NATURE, SIZE, SHAPE AND DISTRIBUTION OF PHASES IN THE ROCK WHICH IT DESCRIBES. THE EXAMINATION OF MINERALS IS CARRIED OUT EITHER ON THIN LAMINA IN ORDER TO IDENTIFY THEM OR ON POLISHED SECTIONS IN ORDER THE RECOGNIZE THEM AFTER CHEMICAL ATTACK. DEPENDING ON AVERAGE HARDNESS, TIN ALUMINATE OR OXIDE IN SUSPENSION IN ALCOHOL IS CHOSEN FOR THE POLISHING OF SECTIONS. THE THIN LAMINA ARE PREPARED IN THICKNESS PROPORTIONATE TO THE DIMENSION OF THE PHASES IN THE ROCK: 30 FOR A NATURAL CRYSTALLINE ROCK, 15 FOR CLINKER, 10 FOR CEMENT PASTE. MACRO- AND MICROGRAPHY ILLUSTRATE CERTAIN ASPECTS OF THE SILICATES AND ALUMINATES ATTACKED BY VARIOUS REAGENTS. IN STUDYING THE HYDRATION OF CEMENT THE DIFFICULTY ARISING FROM THE SIZE OF GRAINS IS OVERCOME BY USING SPECIAL GRADING SYSTEMS IN WHICH THE DISTRIBUTION OF ANHYDRIDE AND HYDRATED PRODUCTS IS SHOWN. /LCPC/RRL/A/]]></description>
      <pubDate>Sun, 28 Aug 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/98531</guid>
    </item>
    <item>
      <title>THE INFLUENCE OF VARIOUS SULPHATES UPON THE SETTING AND HARDENING OF CEMENTS</title>
      <link>https://trid.trb.org/View/101578</link>
      <description><![CDATA[WITH REFERENCE TO THE RESULTS OF LITERATURE STUDIES AND NUMEROUS INVESTIGATIONS CONDUCTED AT THE INSTITUT FUR GESTEINSHUTTENKUNDE (INSTITUTE FOR ROCK PRODUCTS TECHNOLOGY), THE ARTICLE DESCRIBES THE EFFECT OF THE SULPHATE CONTENT, IN TERMS OF TYPE AND QUANTITY, UPON THE SETTING AND HARDENING OF CEMENTS. THE FORMATION OF AN ENVELOPE OF ETTRINGITE-LIKE PHASES ON THE SURFACE OF THE ALUMINOFERRITIC PHASES OF THE CLINKER AND THE ALUMINA IN THE GRANULATED BLASTFURNACE SLAB OR THE POZZOLANA IS THE CAUSE OF THE RETARDATION OF SETTING WHEN SULPHATE IS ADDED TO CEMENTS CONFORMING TO THE GERMAN STANDARD SPECIFICATIONS DIN 1164 AND DIN 1167 RESPECTIVELY. ONLY WHEN THE SULPHATE CONCENTRATION IN THE DISSOLVED PHASE FALLS SHORT OF THE CONCENTRATION NEEDED TO FORM ETTRINGITE WILL THE INITIALLY FORMED ETTRINGITE-LIKE PHASES BE CONVERTED INTO MONOSULPHATE HYDRATES OR THE SOLID SOLUTIONS THEREOF WITH TETRACALCIUM ALUMINOFERRITE HYDRATES, THE ALUMINOFERRITIC PHASE BEING CONSUMED IN THIS PROCESS OF CONVERSION. THIS INTERPRETATION OF THE SETTING RETARDATAON ALSO MAKES POSSIBLE AN EXPLANATION FOR THE OPTIMIZATION OF THE STRENGTH DEVELOPMENT BY THE ADDITION OF SULPHATE, INASMUCH AS THE FORMATION OF ETTRINGITE IS ASSOCIATED WITH SWELLING AND SHOULD VERY LARGELY HAVE BEEN COMPLETED AT THE END OF THE SETTING PROCESS. IN CONTRAST WITH THIS, IN THE CASE OF SUPERSULPHATED CEMENT THE FORMATION OF ETTRINGITE TAKES PLACE WITHOUT BEING ACCOMPANIED BY SWELLING AND CONTRIBUTES TO THE STRENGTH. THE USE OF PURE OR GYPSUM-CONTAINING ANHYDRITE INSTEAD OF DIHYDRATE RESULTS IN SOME INSTANCES IN A MARKED IMPROVEMENT OF THE TECHNOLOGICAL PROPERTIES OF THE CEMENTS CONFORMING TO DIN 1164, DIN 1167 AND DIN 4210, AS THE HYDRATION IS ACCELERATED THE CAUSE OF THIS IS THE LOWER RATE OF SOLUTION OF THE ANHYDRITE AND ITS SMALLER SPECIFIC VOLUME. /AUTHOR/]]></description>
      <pubDate>Fri, 01 Jul 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/101578</guid>
    </item>
    <item>
      <title>COPING WITH STRESS GIVES KARAWANKEN TUNNELLERS A HEADACHE</title>
      <link>https://trid.trb.org/View/359433</link>
      <description><![CDATA[This article describes the Karawanken Tunnel between Austria and Yugoslavia. Extensive deformations caused by high tectonic stress, swelling anhydrite, water and methane gas have given the tunnellers driving the 7.8km Karawanken road tunnel many headaches. A redesigned ventilation system, part longitudinal and part transverse, has cut costs by saving the need for two deep ventilation shafts.]]></description>
      <pubDate>Mon, 30 Sep 1991 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/359433</guid>
    </item>
    <item>
      <title>ANOTHER LOOK AT THE PORTLAND CEMENT/CHEMICAL ADMIXTURE INCOMPATIBILITY PROBLEM</title>
      <link>https://trid.trb.org/View/296297</link>
      <description><![CDATA[Specifications calling for the use of admixtures in concrete often result in strange occurrences, that is, rapid set, accelerated stiffening, increase in time of set, lack of water reduction.  This paper addresses the effect of the composition of the cement and that of the chemical admixture on incompatibility with respect to the problems of rapid set and the accererated slump loss.  There is increasing use of natural anyhydrate (CaSO4) as a substitute or partial replacement for gypsum (CaSO4 .2H20) in the manufacture of portland cement.  Data is presented that shows why large amounts of natural anhydrite in portland cement can cause incompatibility problems in the presence of chemical admixtures.  The rate of solution of the anhydrite, which is much slower than that of gypsum or calcium sulfate hemihydrate, is further retarded in the presence of chemical admixtures, which leads to a "sulfate-starved" system in the concrete, often producing rapid set and an increase in rate of concrete slump loss.]]></description>
      <pubDate>Fri, 30 Jun 1989 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/296297</guid>
    </item>
    <item>
      <title>THE INFLUENCE OF GROUND AND GROUNDWATER GEOCHEMISTRY ON CONSTRUCTION IN THE MIDDLE EAST</title>
      <link>https://trid.trb.org/View/270173</link>
      <description><![CDATA[Many parts of the world's extensive hot drylands pose significant problems for the civil engineer because of chemically aggressive and changing ground conditions.  The most important areas are generally the broad flat coastal strips of more recent sediment, for these commonly contain abundant sulphate as gypsum and anhydrite and have widespread surface of near-surface crusts of halite. The coastal water and groundwater in these regions are usually sulphate and chloride rich, moving slowly through the sediments because of rapid evaporation of the groundwater via the capillary fringe into the drier atmosphere.  This movement of groundwater accelerates solution and precipitation of the more soluble minerals, the greater the flow rate the more rapid the compositional change in the sediments -sufficiently rapidly to be of engineering significance.  The engineering works themselves can effect significant changes in the ground chemistry and this is most often brought about by changing the position of the water table or the capillary fringe, by dewatering, or raising ground levels by depositing fill. In addition to the significant effect of salts on results of standard engineering tests, the other most likely problems created by the chemical changes are: settlement due to solution in flowing groundwater, heave due to crystallization from groundwater or by reaction between soils and groundwater, and the creation of a chemically aggressive environment in foundations.  The properties of these groundwater-soil systems are reviewed from the point of view of field observations and some large-scale experiments which give indications of the magnitudes and rates of the chemical processes.  Two case histories are cited by way of illustration -Dubai dry dock anddthe harbour works at Mina Jebel Ali, Dubai.  The dry dock represents an example of settlement effected by the solution of gypsum from lithified sediments through which seawater was passing, and the harbour works show how groundwater and fill chemistry have been changed in the few years required for the construction works.  (Author/TRRL)]]></description>
      <pubDate>Sat, 31 May 1986 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/270173</guid>
    </item>
    <item>
      <title>SOME PRELIMINARY TEST DATA ON CEMENT-PFA-ANHYDRITE MIXES</title>
      <link>https://trid.trb.org/View/216648</link>
      <description><![CDATA[Cement-stabilized pfa is commonly used as a load-bearing fill for civil engineering purposes.  Anhydrite is often used for similar purposes in the mining industry.  A series of compressive strength tests were carried out on combinations of these three materials to determine their potential as moderate-to high-strength fills.  The tests were carried out on 38 mm dia by 75 mm long specimens prepared by static compaction techniques.  Attempts to stabilize pfa using anhydrite showed little potential for increasing the load-bearing capacity of pfa.  However, a study of the combination of cement and anhydrite in the stabilization of pfa showed these two materials to be complementary in increasing the compressive strength of compacted stabilized pfa compared with using just cement or just anhydrite as the stabilizing agent.  The 14, 28 and 56 day strengths of cement-bound pfa were more than doubled by the replacement of 1.4% cement by weight with 10% anhydrite by weight.  The addition of higher proportions of anhydrite could decrease this enhanced strength or give only a marginal increase.  Long-term tests after a curing period of one year showed no apparent deterioration in strength. (Author/TRRL)]]></description>
      <pubDate>Wed, 31 Jul 1985 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/216648</guid>
    </item>
    <item>
      <title>THE MEASUREMENT OF THE HEAT OF HYDRATION OF CEMENT</title>
      <link>https://trid.trb.org/View/30516</link>
      <description><![CDATA[The heat of solution method is briefly described, and the results obtained in five test cycles are detailed. This method is used to calculate the heat of hydration by distinguishing between the heat of solution in an acid mixture, of anhydrous cement and hydrated cement kept for a period of time at a constant temperature. The testing is usually carried out on samples kept at the same temperature and during the same periods of time as for strength tests but, as with the latter, it can be applied to samples kept under different conditions. The first test program consisted of the measurement of the heat of hydration at 3.7 28 days for portland cement and at 28 days for pozzolana cement. The second test series carried out on portland cement, pozzolana and a blast furnace cement, included the measurement of the CaO (calcium oxide) and loss on ignition. The third cycle aimed at obtaining consistency in the basic measurement of the heat of solution of anhydrous and hydrated samples and establishing the most suitable method for calculating the corrected temperature rise. The fourth series of tests was designed to control the calibration of the calorimeter and to apply the procedure which has given satisfactory results for portland cement, to pozzolana and blastfurnace cements. The good consistency obtained for the heat of solution of anhydrous samples confirmed that the method did not involve operational difficulties when applied to cements with slow solution rates. The fifth cycle of tests evaluated the method with special reference to blastfurnace cement. A summary of standard deviations from the general average values obtained in the test cycles is tabulated. The results indicate that for all types of cement and all ages under consideration, the final standard deviations of the values obtained in different laboratories are less than +/- 2 cal/g.]]></description>
      <pubDate>Wed, 21 Apr 1976 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/30516</guid>
    </item>
    <item>
      <title>THE PHASES OF THE CALCIUM SULPHATE AND HYDRATED CALCIUM SULPHATE SYSTEM</title>
      <link>https://trid.trb.org/View/101521</link>
      <description><![CDATA[THE PRESENT STATE OF KNOWLEDGE CONCERNING THE PHASES OF THE SYSTEM CALCIUM SULFATE AND CALCIUM SULFATE HYDRATE IS REVIEWED IN THE ARTICLE. BESIDES THE RELEVANT WESTERN LITERATURE, RUSSIAN PUBLICATIONS ARE ALSO CONSIDERED. THERE IS A CONSIDERABLE MEASURE OF AGREEMENT AS TO THE EXISTENCE AND CHARACTERIZATION OF THE CALCIUM SULFATE DIHYDRATE, CALCIUM SULFATE HEMIHYDRATE AND ANHYDRITE II PHASES. RESEARCH RESULTS RELATING TO THE PREPARATION, EXISTENCE, AND PROPERTIES OF ANHYDRITE III ARE DISCUSSED, AS ARE ALSO THE THERMODYNAMIC RELATIONS BETWEEN THE INDIVIDUAL PHASES. THE DIFFERENT CONDITIONS FOR PREPARING THE PURE PHASES IN THE LABORATORY AND FOR THE TECHNICAL PRODUCTION OF THE CALCINED GYPSUM PLASTERS ARE INDICATED. /AUTHOR/]]></description>
      <pubDate>Tue, 01 Sep 1970 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/101521</guid>
    </item>
    <item>
      <title>SOIL STABILIZATION BY CHEMICAL METHODS</title>
      <link>https://trid.trb.org/View/119604</link>
      <description><![CDATA[ATTEMPTS TO FIND A GENERAL FORMULATION OF SODIUM ADDITIVES FOR ALL SOIL TYPES BY COMBINING SODIUM HYDROXIDE AND SODIUM SULFITE AT VARIOUS MOLAR RATIOS HAVE NOT BEEN SUCCESSFUL. PRETREATMENT OF HEAVY CLAYS WITH 1% OCTYLAMINE OR FERRIC CHLORIDE (0.1%) INCREASES THE STRENGTH OF CLAY STABILIZED WITH 5% CEMENT AND 1% SODIUM HYDROXIDE BY REDUCING THE VOLUME EXPANSION OF SOIL DURING IMMERSION. THE REMOVAL OF ORGANIC MATTER FROM AN ORGANIC-CONTAINING SAND CONFIRMS THE BELIEF THAT THE ORGANIC MATTER PRESENT IN THE SAND IS THE ONLY REASON FOR THE INEFFECTIVENESS OF TREATMENT OF THIS SOIL WITH CEMENT AND PREVIOUSLY USED ADDITIVES. CALCIUM SULFATE ANHYDRITE, GYPSUM, AND MAGNESIUM SULFATE ARE VERY EFFECTIVE IN INCREASING STRENGTH OF ORGANIC SAND STABILIZED WITH CEMENT. STUDY OF THE EFFECTS OF SODA-TO-SILICA RATIO IN SODIUM SILICATES AS ADDITIVES TO CEMENT-STABILIZED SILT INDICATES THAT THE SILICATES OF HIGH SODA CONTENT ARE VERY EFFECTIVE IN STRENGTH IMPROVEMENT.]]></description>
      <pubDate>Mon, 16 Feb 1970 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/119604</guid>
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