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5.1 This test method is useful in indicating the differences in abrasion resistance between various building stones. This test method also provides one element in comparing stones of the same type.NOTE 1: Test Method C1353/C1353M is an alternative method to evaluate abrasion resistance for stone subjected to foot traffic, but is not applicable for hard and coarse-grained stones such as granite. Preliminary assessments by Subcommittee C18.03 indicate it results in similar Ha values as established by this method.1.1 This test method covers the determination of abrasion resistance of all types of stones for floors, steps, and similar uses where the wear is caused by foot traffic.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.1.2.1 Exception—The formula for calculation of the result of this test method relies on the use of SI units; all measurements of weight in this test method shall be recorded in SI units. See 10.1 and 11.1.1.3 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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This test method provides a means of evaluating and comparing development of corrosion at scribe on painted/coated flat test panels after exposure to corrosive environments.1.1 This test method covers the measurement of rust creepage area from a scribe line on painted/coated flat test panels after exposure to corrosive environments. This test method has the advantage of simplicity and ease of use. Expensive equipment is not required, and the results are more accurate than visual evaluation but not as precise as advanced digital imaging. 1.2 This test method uses visual imaging software to determine the area damaged by rust creepage from the scribe. 1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 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.

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1.1 This test method covers the determination of the test period of frost immunity of concrete specimens as measured by the length of time of water immersion required to produce critical dilation when subjected to a prescribed slow-freezing procedure. 1.2 The values stated in SI units are to be regarded as the 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 and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 Linear shrinkage, as used in this test method, refers to the change in linear dimensions that has occurred in test specimens after they have been subjected to soaking heat for a period of 24 h and then cooled to room temperature.4.2 Most insulating materials will begin to shrink at some definite temperature. Usually the amount of shrinkage increases as the temperature of exposure becomes higher. Eventually a temperature will be reached at which the shrinkage becomes excessive. With excessive shrinkage, the insulating material has definitely exceeded its useful temperature limit. When an insulating material is applied to a hot surface, the shrinkage will be greatest on the hot face. The differential shrinkage which results between the hotter and the cooler surfaces often introduces strains and may cause the insulation to warp. High shrinkage may cause excessive warpage and thereby may induce cracking, both of which are undesirable. High shrinkage may also open gaps at the insulation joints to an excessive extent rendering the application less efficient and more hazardous. In order to predict the limit of permissible shrinkage in service, the degree of linear shrinkage to be tolerated by specimens of an insulating material when subjected to soaking heat must be determined from experience.4.3 It is recognized that a fixed relation between linear shrinkage under soaking heat and actual shrinkage in service cannot be established for different types of insulating materials. Generally the amount of shrinkage increases with time of exposure. The amount and rate of increase varies from one material to another. In addition, the various types of materials may have different amounts of maximum permissible shrinkage. Therefore, each product must define its own specific limits of linear shrinkage under soaking heat.1.1 This test method covers the determination of the amount of linear shrinkage and other changes that occur when a preformed thermal insulating material is exposed to soaking heat. This test method is limited to preformed high-temperature insulation that is applicable to hot-side temperatures in excess of 150°F (66°C), with the exception of insulating fire brick which is covered by Test Method C210.1.2 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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5.1 This test method provides a means to quantify the abrasion resistance of dimension stone and may be related to end-use performance, or used to comparatively rank material performance, or both. The resistance of dimension stone to abrasion, as measured on a testing machine in the laboratory, is generally only one of several factors contributing to wear performance as experienced in the actual use of the material. Calculation of predicted life should not be based on specific abrasion data alone.5.2 The resistance of dimension stone to abrasion may be affected by factors including test conditions; type of abradant; pressure between the specimen and abradant; mounting of the specimen; and type, kind, or amount of finishing materials.5.3 Abrasion tests utilizing the rotary platform abraser may be subject to variation due to changes in the abradant during the course of specific tests. Depending on abradant type and test specimen, the abrading wheel surface may change (that is, become clogged) due to pick-up of finishing or other materials from test specimens. To reduce this variation, the abrading wheels may require resurfacing.1.1 This test method covers the establishment of an index of abrasion resistance by determination of loss of volume resulting from abrasion of dimension stone as described in Terminology C119 and is based on Guide G195.1.2 The values stated in either inch-pound units or SI units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.1.2.1 Exception—The formula for calculation of the result of this test method relies on the use of SI units; all measurements of weight in this test method shall be recorded in SI units.1.2.2 Exception—As the equipment used in this test method was designed and initially fabricated using dimensions in inch-pound units, the values of equipment dimensions stated in SI units have been given as exact conversions to the nearest 0.1 mm.1.3 This test method uses a rotary platform abraser to determine the loss in volume of dimension stone caused by abrasion under controlled conditions.1.4 This test method is useful in indicating the differences in abrasion resistance between the various dimension stones. This test method provides one element in comparing stones of the same type.1.5 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.1.6 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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4.1 Finite element analysis is a valuable tool for evaluating the performance of metallic stents and in estimating quantities such as stress, strain, and displacement due to applied external loads and boundary conditions. FEA of stents is frequently performed to determine the worst-case size for experimental fatigue (or durability) testing and differentiation of performance between designs. A finite element analysis is especially valuable in determining quantities that cannot be readily measured.1.1 Purpose—This guide establishes recommendations and considerations for the development, verification, validation, and reporting of structural finite element models used in the evaluation of the performance of a metallic vascular stent design undergoing uniform radial loading. This standard guide does not directly apply to non-metallic or absorbable stents, though many aspects of it may be applicable. The purpose of a structural analysis of a stent is to determine quantities such as the displacements, stresses, and strains within a device resulting from external loading, such as crimping or during the catheter loading process, and in-vivo processes, such as expansion and pulsatile loading.1.2 Limitations—The analysis technique discussed in this guide is restricted to structural analysis using the finite element method. This document provides specific guidance for verification and validation (V&V) of finite element (FE) models of vascular stents subjected to uniform radial loading using ASME V&V40 as the basis for developing and executing risk-informed V&V plans.1.2.1 Users of this document are encouraged to read ASME V&V40 for an introduction to risk-informed V&V, and to read ASME V&V10 for further guidance on performing V&V of computational solid mechanics models. This document is not intended to cover all aspects of developing a finite element model of radial deformation of a stent. It is intended for a FE analyst with structural modeling experience.1.2.2 While risk-informed V&V is encouraged, it is not required. Analysts may utilize alternate V&V methods. The methodology employed should be developed by knowledgeable stakeholders with consideration as to the expectations and requirements of internal teams and external bodies that will assess the performance of the stent and the credibility of the model used to make performance predictions.1.2.3 If an alternative V&V method is employed, then Sections 5, 6, 7, and 10 that follow ASME V&V40 guidelines may be viewed as suggestions only. Other portions of the document that refer to question of interest, risk, and context of use may be viewed in the same manner.1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for informational purposes only.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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4.1 This method provides a means of evaluating and comparing basic corrosion performance of the substrate, pretreatment, or coating system, or combination thereof, after exposure to corrosive environments.1.1 This test method covers the treatment of previously painted or coated specimens for accelerated and atmospheric exposure tests and their subsequent evaluation in respect to corrosion, blistering associated with corrosion, loss of adhesion at a scribe mark, or other film failure.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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 whoever uses this standard to consult and establish appropriate safety and health 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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1.1 This specification covers the classification, processing, and properties of nuclear grade graphite billets with dimensions sufficient to meet the designer’s requirements for reflector blocks and core support structures, in a high temperature gas cooled reactor. The graphite classes specified here would be suitable for reactor core applications where neutron irradiation induced dimensional changes are not a significant design consideration.1.2 The purpose of this specification is to document the minimum acceptable properties and levels of quality assurance and traceability for nuclear grade graphite suitable for components subjected to low irradiation dose. Nuclear graphites meeting the requirements of Specification D7219 are also suitable for components subjected to low neutron irradiation dose.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 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 Regulations prescribing the test procedures for hazardous materials packaging allow for the substitution of non-hazardous fill materials for packaging performance tests with certain limitations prescribed and guidance offered (see 49 CFR 178.602(c)). This regulatory guidance has proven to be flexible enough, in common industry practice, to produce variations in the selection of fill materials for package performance tests sufficient to cause inconsistent and non-repeatable test results. This variation creates significant problems in product liability, packaging selection and regulatory enforcement in this highly regulated industry. Use of this guide should enhance uniformity in test procedures.5.2 Consistent and repeatable test results coupled with clear test fill product descriptions will enhance transportation safety by simplifying packaging selection. This will also increase the general level of confidence that package testing, manufacture, and use are being guided by sound, generally accepted engineering principles. It also aids in clarifying expectations between the packaging industry and the regulatory authorities.5.3 The guide will be used by packaging manufacturers and packaging test labs to create packaging test plans that meet customer needs and conform to the HMR. In addition, for the user of a packaging, certain information about the type and physical characteristics of the material used to test the packaging must be available in the test report and/or notification instruction to allow evaluation of whether a particular packaging was tested with a substitute material appropriate for the hazardous material to be shipped.1.1 The purpose of this guide is to clarify the selection, use, and description criteria of non-hazardous particulate solid substitutes used to replace hazardous materials for the purpose of performance testing packagings. This includes identification of the physical parameters of substitute non-hazardous solid test fill materials that may affect packaging performance and test results and should be considered when selecting and describing a test fill material that conforms to the requirements of the Hazardous Materials Regulations (HMR). This guide is intended for use with package testing procedures for particulate solid materials that have flow characteristics. It is not intended for use with hazardous articles.1.2 This guide provides information to assist packaging users, manufacturers, and performance testing service suppliers regarding the types of physical properties that should be considered when selecting substitute filling substances for the testing, certification and manufacture of packagings under the United Nations packaging protocols (UN Recommendations on the Transport of Dangerous Goods-Model Regulations) as adopted by US DOT in 49 CFR HMR.1.3 This guide provides the suggested minimum information concerning the physical characteristics of the filling substances that should be documented in the certification test report and notification to users to allow for test repeatability and analysis, and to provide guidance to the user of a packaging of pertinent physical differences between potential hazardous lading and the filling substance with which the packaging was tested.1.4 This guide does not purport to address regulatory requirements regarding the compatibility of filling substances with transport packagings. Compatibility requirements must be assessed separately, but it should be noted that under certain national and international dangerous goods regulations, the selection of the filling substances for package performance testing may be prescribed with respect to chemical compatibility requirements.NOTE 1: Under the US HMR determination of packaging compatibility with a particular hazardous fill material is “the responsibility of the person offering the hazardous material for transportation” as prescribed in 49 CFR § 173.24(e).1.5 When testing packaging designs intended for hazardous materials (dangerous goods), the user of this guide shall be trained in accordance with 49 CFR §172.700 and other applicable hazardous materials regulations such as the ICAO Technical Instructions, IMDG Code, other applicable national or international dangerous goods regulations that govern the testing, manufacture and use of packagings authorized for the transportation of dangerous goods, and carrier rules such as the IATA Dangerous Goods Regulations.1.6 The units of measurement are consistent with the HMR.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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5.1 Regulations prescribing the test procedures for hazardous materials packaging allow for the substitution of non-hazardous fill materials for packaging performance tests with certain limitations as outlined in 49 CFR 178.602(c). This regulatory guidance has proven to be flexible enough, in common industry practice, to produce variations in the selection of fill materials for package performance tests that may cause inconsistent and non-repeatable test results. This variation has the potential to create significant problems in product liability, packaging selection, and regulatory enforcement in this highly regulated industry. Use of this guide should enhance uniformity in test procedures.5.2 Consistent and repeatable test results coupled with clear test fill product descriptions will enhance transportation safety by simplifying packaging selection. This will also increase the general level of confidence that package testing, manufacture and use are being guided by sound, generally accepted engineering principles. It also aids in clarifying expectations between the packaging industry and the regulatory authorities.5.3 The guide will be used by packaging manufacturers, and packaging test labs to create packaging test plans that meet customer needs and conform to the HMR under the widest possible situational circumstances. In addition, for the user of a packaging, certain information about the type and physical characteristics of the material used to test the packaging must be available in the test report and/or notification instruction to allow them to evaluate whether a particular packaging was tested with a substitute material appropriate for the hazardous material to be shipped.5.4 For more information on the UN certification tests, refer to Guide D4919. For guidance on determining the appropriate fill materials for preparing samples for UN certification testing with solids reference Guide D8135. For conditioning of plastic packaging designs reference Guide D7790.1.1 This guide is intended to clarify the selection, use, and description criteria of non-hazardous liquid substitutes used to replace liquid hazardous materials on packagings designs being subjected to United Nations (UN) performance-oriented packaging certification as required by United States Department of Transportation Title 49 Code of Federal Regulations (49 CFR) and the United Nations Recommendations on the Transport of Dangerous Goods (UN). This includes identification of the physical parameters of substitute non-hazardous liquid test fill materials that may affect packaging performance and test results and should be considered when selecting and describing a test fill material that conforms to the requirements of the Hazardous Materials Regulations (HMR).1.2 This guide provides information to assist packaging users, manufacturers, and performance testing service suppliers regarding the types of physical properties that should be considered when selecting substitute liquid filling substances for the testing, certification, and manufacture of packagings under the United Nations packaging protocols as adopted by US DOT in 49 CFR HMR..1.3 This guide provides the suggested minimum information concerning the physical characteristics of the filling substances that should be documented in the certification test report and notification to users to allow for test repeatability and analysis. Attention should be paid to the differences in physical characteristics of the substance used in the test compared to the materials transported.1.4 This guide does not purport to address regulatory requirements regarding the compatibility of filling substances with transport packagings. Compatibility requirements must be assessed separately, but it should be noted that under certain national and international dangerous goods regulations, the selection of the filling substances for package performance testing may be prescribed with respect to chemical compatibility requirements.NOTE 1: Under the US HMR determination of packaging compatibility with a particular hazardous fill material is “the responsibility of the person offering the hazardous material for transportation” as prescribed in 49 CFR § 173.24(e).1.5 The units of measurement are consistent with the HMR.1.6 When testing packaging designs intended for hazardous materials (dangerous goods), the user of this guide shall be trained in accordance with 49 CFR §172.700 and other applicable hazardous materials regulations such as the ICAO Technical Instructions, IMDG Code, other applicable national or international dangerous goods regulations that govern the testing, manufacture and use of packagings authorized for the transportation of Dangerous Goods, and carrier rules such as the IATA Dangerous Goods Regulations.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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5.1 The Clean Water Act promulgated the implementation of water quality standards and contamination limits for a wide range of pollutants including oil and grease. Specifically, the EPA prohibits “the discharges of oil that cause a film or sheen upon or cause discoloration of the surface of the water.” Several state and local agencies have adopted this statement in addition to setting concentration limits, that is, 15 mg/L or even 5 mg/L. The purpose of this practice is to evaluate the performance of a separator in regards to the regulations and user requirements.5.2 Another purpose of this practice is to establish that a separator containing oil at its rated capacity would still be capable of meeting the above criteria when subjected to run-off.5.3 This practice is not applicable if the influent to a separator contained a sudden release as much higher concentrations would be expected. For this case, see Practice D6157.5.4 This practice is not applicable if the influent to a separator is conveyed by a pumping means.5.5 The data generated in this method is valid for the separators tested only. The results of these tests may be extrapolated to smaller or larger size separators provided that applicable geometric and dynamic similitude are maintained. Where sound engineering method limits the use of extrapolation, that size unit must be subjected to testing.5.6 The flow rate for all the tests must equal the manufacturer's total rated flow for the given separator at a given influent contamination level and for the selected effluent peak contamination concentration.1.1 This practice covers the procedure, any necessary related apparatus, and the sampling technique to be used in determining the performance characteristics of oil/water separators subjected to contaminated run-off.1.2 This practice does not address the determination of the performance characteristics of an oil/water separator subjected to the sudden release of a relatively large quantity of hydrocarbons that may appear, in pure form or at high concentration, in the influent to the separator. In this case, refer to Practice D6157.1.3 This practice does not address the determination of the performance characteristics of an oil/water separator subjected to a mechanically emulsified influent such as provided by a pump.1.4 This practice does not investigate the ability of the separator to handle debris or suspended solids, that is, grit or tree leaves.1.5 While the effluent may meet code requirements for total oil and grease content, this practice does not address the presence of soluble organics, that is, benzene, toluene, ethyl-benzene, and zylene (BTEXs) which may be detected in the effluent. It also does not make any provisions for the effects of detergents, surfactants, soaps, or any water soluble matter (that is, salts), or any portion of an essentially insoluble matter that may be found in solution on separation. (Effects of certain water soluble chemicals or solids may be investigated by adding them to the water at predetermined constant concentrations.)1.6 In order to estimate the effect of water temperature on the performance of the separator, the tests described in this practice must be performed at two water temperatures. The selected temperatures must be at least 10°C (18°F) apart, with the temperature ranging from a minimum of 0°C (32°F) to a maximum of 50°C (122°F).1.7 This practice does not make any provisions for the variation of pH or temperature during a test run. Refer to Appendix X1 for further detail.1.8 This practice can be used with a variety of hydrocarbons. It adopts No. 2 fuel oil with a density2 of 845 kg/m3 (52.73 lbm/ft3) and a viscosity2 of 1.9 to 4.1 centistokes at 40°C (104°F) and SAE 90 lubricating oil with a density2 of 930 kg/m3 (58 lbm/ft3) at 15.5°C (60°F) and a viscosity (see SAE J313) of 13.5 to < 24 centistokes at 100°C (212°F) as the comparative testing media. It is understood that the results obtained from this practice are only directly applicable to No. 2 fuel oil and SAE 90 lubricating oil for the tested concentrations and only careful interpolation or extrapolation, or both, is allowed to other hydrocarbons. Low viscosity or high density hydrocarbons or hydrocarbons that contain a larger fraction of highly soluble compounds may need to be tested separately.NOTE 1: No extrapolation outside the range of the tested influent or effluent oil concentrations is allowed as performance may not be linear. Hence, to establish performance at a higher or lower concentration, the separator shall be tested for that specific condition. In addition, linearity must be established prior to using linear interpolation.1.9 Since regulations are based on effluent total hydrocarbon content, this practice does not set forth any lower limits on oil particle size for the evaluation of separator efficiency. However, a standardized means for mixing oil and water shall be specified to ensure repeatability. It must be noted however that smaller particles, having a greater surface area to volume ratio, rise at a slower rate than their larger counterparts. (Guide F933 requires that 20 % of all oil particles be smaller than or equal to 50 μm and IMO MEPC 60 (30) does not mention any particle size requirements but asks the user to avoid emulsion causing chemicals.)1.10 Although the tests described in this practice intend to simulate contaminated storm water run-off separation requirements, they do not cover all possible applications. It is the end user's responsibility to determine whether his separation requirements are within the scope of this practice.1.11 A product different from the general description herein may be tested and found to be in compliance with the performance criteria set forth.1.12 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.1.13 This practice does not purport to address all the environmental hazards, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate environmentally responsible practices and to determine the applicability of regulatory limitations prior to use.1.14 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.1.15 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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The laboratory fatigue life determined by this standard for beam specimens have been used to estimate the fatigue life of asphalt concrete pavement layers under repeated traffic loading. Although the field performance of asphalt concrete is impacted by many factors (traffic variation, speed, and wander; climate variation; rest periods between loads; aging; etc.), it has been more accurately predicted when laboratory properties are known along with an estimate of the strain level induced at the layer depth by the traffic wheel load traveling over the pavement.Note 1—The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Specification D3666 alone does not completely assure reliable results. Reliable results depend on many factors; following the suggestions of Specification D3666 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.1.1 This test method provides procedures for determining a unique failure point for estimating the fatigue life of 380 mm (14.96 in.) long by 50 mm (1.97 in.) thick by 63 mm (2.48 in.) wide asphalt concrete beam specimens sawed from laboratory or field compacted asphalt concrete, which are subjected to repeated flexural bending.1.2 The between-laboratory reproducibility of this test method is being determined and will be available on or before June 2013. Therefore, this test method should not be used for acceptance or rejection of a material for purchasing purposes.1.3 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.1.4 Units—The values stated in SI units are to be regarded as standard. Other units of measurement included in this standard are for information only.1.5 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.

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5.1 This test method is useful in research and quality control for evaluating insulating materials and systems since they provide for the measurement of the endurance used to compare different materials to the action of corona on the external surfaces. A poor result on this test does not indicate that the material is a poor selection for use at high voltage or at high voltage stress in the absence of surface corona; surface corona is not the same as corona that occurs in internal cavities. (See Test Methods D3382.)5.2 This test method is also useful for comparison between materials of the same relative thickness. When agreed upon between the buyer and the seller, it is acceptable to express any differences in terms of relative time to failure or the magnitude of voltage stress (kV/mm or kV/in.) required to produce failure in a specified number of hours.5.3 It is possible for this test method to also be used to examine the effects of different processing parameters on the same insulating material, such as residual strains produced by quenching, high levels of crystallinity or molding processes that control the concentration and sizes of gas-filled cavities.5.4 The data are generated in the form of a set of values of lifetimes at a voltage. The dispersion of failure times is analyzed using one of the methods below:5.4.1 Weibull Probability Plot.5.4.2 Statistically (see IEEE/IEC 62539-2007 for additional information), to yield an estimate of the central value of the distribution and its standard deviation.5.4.3 Truncating a test at the time of the fifth failure of a set of nine and using that time as the measure of the central tendency. Two such techniques are described in 10.2.5.5 This test method intensifies some of the more commonly met conditions of corona attack so that materials are able to be evaluated in a time that is relatively short compared to the life of the equipment. As with most accelerated life tests, caution is necessary in extrapolation from the indicated life to actual life under various operating conditions in the field.5.6 The possible factors related to failures produced by corona are:5.6.1 Corona eroding the insulation until the remaining insulation can no longer withstand the applied voltage.5.6.2 Corona causing the insulation surface to become conducting due to carbonization, so that failure occurs quickly.5.6.3 Forming of compounds such as oxalic acid crystals causing the surface conductance to vary with ambient humidity. It is possible conductance will be at a sufficient level to reduce the potential gradient at the electrode edge at moderate humidities, and thus cause either a reduction in the amount of corona, or its cessation, thus retarding failure.5.6.4 Corona causing “treeing” within the insulation and consequently accelerating the time to failure.5.6.5 Gases released within the insulation that change its physical dimensions.5.6.6 Changes in the physical properties of an insulating material; embrittlement or cracking, for instance, causing the material to lose flexibility or crack, or both, and thus make it useless.5.7 Tests are often made in open air, at 50 % relative humidity. In cases agreed upon between the buyer and the seller, additional information can be obtained for some materials with tests in circulating air at 20 % relative humidity or less (see Appendix X1).5.7.1 If tests are made in an enclosure, the restriction in the flow of air can trap ozone and influence the results (see Appendix X2).5.7.2 When tests are done outside the standard conditions, the report shall note the deviation and the alternative conditions.5.8 The variability of the time to failure is a function of the consistency of the test parameters, such as voltage levels, which shall be monitored. The Weibull slope factor, β, is recommended as a measure of variability. β is the slope obtained when percent failure is plotted against failure time on Weibull probability paper. Such a plot is called a Weibull Probability Plot (see Fig. 1).FIG. 1 Representative Weibull Plot Showing the First Five Failures of a Group Specimen of Nine.NOTE 1: Plotting percentage are 100 times the average of (n − 1/2 )/N and n/(N + 1). Artificial data were placed on a line (dashed) drawn to illustrate a Weibull line with a β of 4. A second line (not dashed) illustrates the distribution of failure times which are characteristic of materials with very flat volt-time curves, such as mica composites. This line has a β value of 0.7.5.9 The shape of the Weibull Probability Plot can provide additional information. It is possible that a non-straight-line plot will indicate more than one mechanism of failure. For instance, a few unaccountably short time failures in the set indicating a small portion of defective specimens with a different failure mechanism from the rest of the lot.1.1 This test method determines the voltage endurance of solid electrical insulating materials for use at commercial power frequencies under the action of corona (see Note 1). This test method is more meaningful for rating materials with respect to their resistance to prolonged ac stress under corona conditions for comparative evaluation between materials.NOTE 1: The term “corona” is used almost exclusively in this test method instead of “partial discharge,” because it is a visible glow at the edge of the electrode interface that is the result of partial discharge. Corona, as defined in Terminology D1711, is “visible partial discharges in gases adjacent to a conductor.”1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound 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. For specific hazard statements, see Section 7.1.4 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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