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5.1 Thermal power curves are used to evaluate the isothermal hydration kinetics of the combined mixture of different materials during the early period after being mixed with water. These isothermal power curves, or hydration profiles, may provide indications relative to setting characteristics, compatibility of different materials, sulfate balance and early strength development. The isothermal hydration profiles can also be used to evaluate the effects of compositions, proportions, and time of addition of materials as well as curing temperature. Special care must be used in evaluating extended retardation with paste specimens, which have been shown to overestimate the retardation of some mixtures containing cement, SCM, and admixtures.5.2 This procedure can be used to measure the effect of chemical admixtures on the cement hydration profile. In many cases, the addition of chemical admixture changes the kinetics of cement hydration.5.3 Although this technique has been used historically to understand issues related to setting and slump loss, it must be emphasized that isothermal calorimetry results cannot predict concrete performance definitely, either positively or negatively. Extensive verification in concrete at planned dosages and temperatures, and at higher dosages, is needed. Isothermal calorimetry is an effective tool to identify sensitivities, so that concrete testing can be efficiently planned and performed.5.4 This practice provides a means of assessing the relative hydration performance of various test mixtures compared with control mixtures that are prepared in a similar manner.5.5 The procedure and apparatus can be used to monitor the thermal power from pastes and mortars alone or in combination with chemical admixtures.5.6 The isothermal calorimeter described here can be used to measure the thermal power and heat of hydration of mortars prepared independently or obtained by wet sieving from concrete in accordance with Practice C172/C172M.1.1 This practice describes the apparatus and procedure for measuring relative differences in hydration kinetics of hydraulic cementitious mixtures, either in paste or mortar (see Note 1), including those containing admixtures, various supplementary cementitious materials (SCM), and other fine materials by measuring the thermal power using an isothermal calorimeter.NOTE 1: Paste specimens are often preferred for mechanistic research when details of individual reaction peaks are important or for particular calorimetry configurations. Mortar specimens may give results that have better correlation with concrete setting and early strength development and are often preferred to evaluate different mixture proportions for concrete. Both paste and mortar studies have been found to be effective in evaluating concrete field problems due to incompatibility of materials used in concrete mixtures.1.2 This practice does not cover the measurement of heat of hydration. Heat of hydration can be determined according to Test Method C1702.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. (Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.2)1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This method is suitable for determining the total heat of hydration of hydraulic cement at constant temperature at ages up to 7 days to confirm specification compliance.5.2 This method compliments Practice C1679 by providing details of calorimeter equipment, calibration, and operation. Practice C1679 emphasizes interpretation significant events in cement hydration by analysis of time dependent patterns of heat flow, but does not provide the level of detail necessary to give precision test results at specific test ages required for specification compliance.1.1 This test method specifies the apparatus and procedure for determining total heat of hydration of hydraulic cementitious materials at test ages up to 7 days by isothermal conduction calorimetry.1.2 This test method also outputs data on rate of heat of hydration versus time that is useful for other analytical purposes, as covered in Practice C1679.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Use of the SIM decreases the time required for creep to occur and the obtaining of the associated data.5.2 The statements set forth in 1.5 are very important in the context of significance and use, as well as scope of the standard.5.3 Creep test data are used to calculate the creep modulus of materials as a function of time. These data are then used to predict the long-term creep deformation expected of geosynthetics used in drainage applications.NOTE 1: Currently, SIM testing has focused mainly on geonets made from high-density polyethylene. Additional testing on other materials is ongoing.5.4 R+H testing is done to establish the range of creep strains experienced in the brief period of very rapid response following the peak of the load ramp.1.1 This test method covers accelerated testing for compressive creep properties using the stepped isothermal method (SIM).1.2 The test method is focused on geosynthetic drainage materials such as HDPE geonet specimens.1.3  The SIM tests are laterally unconfined tests based on time-temperature superposition procedures.1.4 Ramp and hold (R+H) tests may be completed in conjunction with SIM tests. They are designed to provide additional estimates of the initial rapid compressive creep strain levels appropriate for the SIM results.1.5 This method can be used to establish the sustained load compressive creep characteristics of a geosynthetic that demonstrates a relationship between time-dependent behavior and temperature. Results of this method are to be used to augment results of compressive creep tests performed at 20 ± 1 °C and may not be used as the sole basis for determination of long-term compressive creep behavior of geosynthetic material.1.6 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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6.1 These test methods are useful for research and development, quality assurance, regulatory compliance, and specification acceptance purposes.6.2 The determination of the order of a chemical reaction or transformation at specific temperatures or time conditions is beyond the scope of these test methods.6.3 The activation energy results obtained by these test methods may be compared with those obtained from Test Method E698 for nth order and accelerating reactions. Activation energy, pre-exponential factor, and reaction order results by these test methods may be compared to those for Test Method E2041 for nth order reactions.1.1 Test Methods A, B, and C determine kinetic parameters for activation energy, pre-exponential factor and reaction order using differential scanning calorimetry (DSC) from a series of isothermal experiments over a small (≈10 K) temperature range. Test Method A is applicable to low nth order reactions. Test Methods B and C are applicable to accelerating reactions such as thermoset curing or pyrotechnic reactions and crystallization transformations in the temperature range from 300 K to 900 K (nominally 30 °C to 630 °C). These test methods are applicable only to these types of exothermic reactions when the thermal curves do not exhibit shoulders, double peaks, discontinuities or shifts in baseline.1.2 Test Methods D and E also determines the activation energy of a set of time-to-event and isothermal temperature data generated by this or other procedures1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 8.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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3.1 This test method provides a rapid, inexpensive method for comparing the corrosion resistance of refractories. The isothermal conditions of this test method represent the most severe static corrosion environment possible at the specified test temperature. This test method is suitable for quality control, research and development applications, and for product value studies on similar materials. Tests run at a series of temperatures are often helpful in determining the use temperature limitations of a particular material. Melt-line corrosion results are also a useful indication of relative resistance to both upward and downward drilling corrosion mechanisms. Examination of test specimens also provides information about the tendency for a particular refractory to form stones or other glass defects.3.2 Because this test method is both isothermal and static, and since most glass-contact refractories operate in a dynamic system with a thermal gradient, test results do not directly predict service in a furnace. The effects of differing thermal conductivities, refractory thickness, artificial cooling or insulation upon the refractory thermal gradient, and the erosive action of moving molten glass currents are not evaluated with this test.1.1 This test method covers the determination of the corrosion resistance of refractories in contact with molten glass under static, isothermal conditions.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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Isothermal secant bulk modulus (static bulk modulus) is a property that measures the compressibility of a liquid. The greater the value, the less the compressibility of the liquid.Isothermal secant bulk modulus is employed in the design of high performance hydraulic fluid and braking systems. High bulk modulus is desirable in that the response time of a system is faster when applied pressure more directly effects the action of the system rather than in the compression of the working liquid.If isothermal secant bulk modulus is known as a function of pressure, the data may be used to calculate isothermal tangent bulk modulus and density as a function of pressure. The data may not, however, be used to determine isentropic (dynamic) bulk modulus. That property is usually determined from velocity of sound measurements and differs from isothermal bulk modulus by the ratio of Cp/Cv = γ (the ratio of heat capacity at constant pressure to that at constant volume for the test specimen.1.1 This test method covers the determination of isothermal secant and tangent bulk modulus of liquids which are stable and compatible with stainless steel under the conditions of test.1.2 This test method is designed to be used over the temperature range from -40 to 200°C and from ambient to 68.95 Mpa (10 000 psig).Note 1—Because of the design of the test apparatus, the upper limit of pressure which can be attained is limited by the bulk modulus of the test fluid. Pressures as high as 68.95 Mpa will not be attained for fluids of relatively low bulk modulus at the test temperature.1.3 This test method assumes that the user is proficient in the assembly and use of medium pressure (m/p) threaded and coned fittings which are intended for use at pressures up to 137.9 Mpa (20 000 psig).1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.Note 2—Because hydraulic pressure in the test system is produced by purely mechanical means, the test method is not subject to the hazards associated with systems which are pressurized pneumatically. Even small leaks will result in immediate drop in pressure to ambient without production of a high pressure liquid stream or mist.

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5.1 Non-isothermal stress relaxation, also known as temperature scanning stress relaxation, performed at a specific heating rate, delivers a set of parameters useful to specify the properties of thermo-plastic elastomers. It can also characterize the deterioration of the cross-linked rubber network in a reasonable testing time of a few hours.5.2 Stress relaxation tests are typically performed as time-dependent experiments at constant strain and temperature. It is known that temperature has a strong influence on the relaxation time of rubber. When evaluating ageing behavior such as deterioration of the network, a reliable test using isothermal stress relaxation requires extremely long testing times, for example, days or weeks depending on the application.1.1 This test method is used to determine the non-isothermal stress relaxation, also known as temperature scanning stress relaxation (TSSR). Stress relaxation is a characteristic behavior of rubber materials.1.2 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Rheological properties such as viscosity and storage and loss modulus change rapidly with temperature. High quality determinations of these properties depend upon a stable and well-known temperature of the measuring apparatus.5.2 This test method may be used for research, quality assurance, specification acceptance, and regulatory compliance.1.1 This test method describes the temperature calibration or conformance of rheometers. The applicable temperature range is 0 °C to 80 °C however other ranges may be selected for the purpose at hand.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Use of the Stepped Isothermal Method decreases the time required for creep to occur and the obtaining of the associated data.5.2 The statements set forth in 1.6 are very important in the context of significance and use, as well as scope of the standard.5.3 Creep test data are used to calculate the creep modulus of materials as a function of time. These data are then used to predict the long-term creep deformation expected of geosynthetics used in reinforcement applications.NOTE 1: Currently, SIM testing has focused mainly on woven and knitted geogrids and woven geotextiles made from polyester, aramid, polyaramid, poly-vinyl alcohol (PVA), and polypropylene yarns and narrow strips. Additional correlation studies on other materials are needed.5.4 Creep-rupture test data are used to develop a regression line relating creep stress to rupture time. These results predict the long-term rupture strength expected for geosynthetics in reinforcement applications.5.5 Tensile testing is used to establish the ultimate tensile strength (TULT) of a material and to determine elastic stress, strain, and variations thereof for SIM tests.5.6 Ramp and Hold (R+H) testing is done to establish the range of creep strains experienced in the brief period of very rapid response following the peak of the load ramp.1.1 This test method covers accelerated testing for tensile creep, and tensile creep-rupture properties using the Stepped Isothermal Method (SIM).1.2 The test method is focused on geosynthetic reinforcement materials such as yarns, ribs of geogrids, or narrow geotextile specimens.1.3 The SIM tests are laterally unconfined tests based on time-temperature superposition procedures.1.4 Tensile tests are to be completed before SIM tests and the results are used to determine the stress levels for subsequent SIM tests defined in terms of the percentage of Ultimate Tensile Strength (TULT). Additionally, the tensile test can be designed to provide estimates of the initial elastic strain distributions appropriate for the SIM results.1.5 Ramp and Hold (R+H) tests may be completed in conjunction with SIM tests. They are designed to provide additional estimates of the initial elastic and initial rapid creep strain levels appropriate for the SIM results.1.6 This method can be used to establish the sustained load creep and creep-rupture characteristics of a geosynthetic. Results of this method are to be used to augment results of Test Method D5262 and may not be used as the sole basis for determination of long-term creep and creep-rupture behavior of geosynthetic material.1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 These test methods are used to assess the chemical (pozzolanic or hydraulic) reactivity of SCMs over a curing time of 7 days. The results of these test methods can be used to estimate the potential contribution of a SCM to the development of strength, or other properties such as lower permeability, when used with portland cement. However, the test results are not a substitute for direct measurement of the same properties of concrete made with that SCM.5.2 The calcium hydroxide, calcium carbonate, potassium sulfate, and potassium hydroxide are combined in proportions to provide a paste where the dissolved ions from these components simulate the pore solution in a portland cement system.5.3 The pastes are cured at 40 °C to accelerate the rate of reaction of slowly reactive SCMs.5.4 These test methods allow for the direct measurement of the hydraulic or pozzolanic reactivity of a potential SCM. These test methods are also suitable for screening purposes in the development and research of SCMs for use in portland cement-based systems. Furthermore, these test methods may be used in manufacturing control of portland cement-based products for assessing the hydraulic or pozzolanic reactivity of a SCM component.5.5 These test methods are based on the work by Avet et al.4 and are a result of the work of RILEM Technical Committee 267 – Tests for Reactivity of Supplementary Cementitious Materials.5 The test methods are based on established correlations between strength development and evolution of heat and binding of water for SCMs covered by Specifications C618, C989/C989M, and C1240, and by Guide C1709. For other alternative SCMs, the validity of such correlations has not been established.5.6 There is no requirement to use Method A and Method B for a given application. In many instances the choice is based on the user’s determination of available equipment. Method A can also provide an indication of rate of reactivity because measurements are taken continuously during the test period, while Method B provides the level of reactivity up to a single point in time.1.1 These two alternative test methods are used to assess the chemical reactivity of a supplementary cementitious material (SCM) as determined by measurements of cumulative heat release or bound water content of hydrated pastes composed of the SCM, calcium hydroxide, calcium carbonate, potassium sulfate, and potassium hydroxide cured at 40 °C for 3 and 7 days.1.1.1 These two test methods do not distinguish between hydraulic and pozzolanic reactivity.1.2 The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.3 The text of the standard refers to notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. (Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.)21.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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