4.1 The procedures outlined will provide data that can be used to evaluate the relative performance of wall, floor, and roof constructions under conditions representative of those sustained in actual service when subjected to impact by a heavy blunt object. See Test Method E661 for evaluation of floor and roof sheathing and Practice E73 for evaluation of roof trusses.4.2 The method is intended to be applied to relatively light construction, including, but not limited to, wood floor and roof systems, partitions framed with wood or steel studs, steel floor or roof decking systems, steel siding and wall panels, or thin concrete and masonry walls or slabs and similar assemblies.1.1 This test method covers the measurement of the relative resistance of wall, floor, and roof construction to impact loading. The test is not applicable to doors.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 The first-peak strength characterizes the flexural behavior of the fiber-reinforced concrete up to the onset of cracking, while residual strengths at specified deflections characterize the residual capacity after cracking. Specimen toughness is a measure of the energy absorption capacity of the test specimen. The appropriateness of each parameter depends on the nature of the proposed application and the level of acceptable cracking and deflection serviceability. Fiber-reinforced concrete is influenced in different ways by the amount and type of fibers in the concrete. In some cases, fibers may increase the residual load and toughness capacity at specified deflections while producing a first-peak strength equal to or only slightly greater than the flexural strength of the concrete without fibers. In other cases, fibers may significantly increase the first-peak and peak strengths while affecting a relatively small increase in residual load capacity and specimen toughness at specified deflections.5.2 The first-peak strength, peak strength, and residual strengths determined by this test method reflect the behavior of fiber-reinforced concrete under static flexural loading. The absolute values of energy absorption obtained in this test are of little direct relevance to the performance of fiber-reinforced concrete structures since they depend directly on the size and shape of the specimen and the loading arrangement.5.3 The results of this test method may be used for comparing the performance of various fiber-reinforced concrete mixtures or in research and development work. They may also be used to monitor concrete quality, to verify compliance with construction specifications, obtain flexural strength data on fiber-reinforced concrete members subject to pure bending, or to evaluate the quality of concrete in service.5.4 The results of this standard test method are dependent on the size of the specimen.NOTE 5: The results obtained using one size molded specimen may not correspond to the performance of larger or smaller molded specimens, concrete in large structural units, or specimens sawn from such units. This difference may occur because the degree of preferential fiber alignment becomes more pronounced in molded specimens containing fibers that are relatively long compared with the cross-sectional dimensions of the mold. Moreover, structural members of significantly different thickness experience different maximum crack widths for a given mid-span deflection with the result that fibers undergo different degrees of pull-out and extension.1.1 This test method evaluates the flexural performance of fiber-reinforced concrete using parameters derived from the load-deflection curve obtained by testing a simply supported beam under third-point loading using a closed-loop, servo-controlled testing system.1.2 This test method provides for the determination of first-peak and peak loads and the corresponding stresses calculated by inserting them in the formula for modulus of rupture given in Eq 1. It also requires determination of residual loads at specified deflections, the corresponding residual strengths calculated by inserting them in the formula for modulus of rupture given in Eq 1 (see Note 1). It provides for determination of specimen toughness based on the area under the load-deflection curve up to a prescribed deflection (see Note 2) and the corresponding equivalent flexural strength ratio.NOTE 1: Residual strength is not a true stress but an engineering stress computed using simple engineering bending theory for linear elastic materials and gross (uncracked) section properties.NOTE 2: Specimen toughness expressed in terms of the area under the load-deflection curve is an indication of the energy absorption capability of the particular test specimen, and its magnitude depends directly on the geometry of the test specimen and the loading configuration.1.3 This test method utilizes two preferred specimen sizes of 100 mm by 100 mm by 350 mm [4 in. by 4 in. by 14 in.] tested on a 300 mm [12 in.] span, or 150 mm by 150 mm by 500 mm [6 in. by 6 in. by 20 in.] tested on a 450 mm [18 in.] span. A specimen size different from the two preferred specimen sizes is permissible.1.4 Units—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.1.5 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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5.1 This test method is used for research, design, service evaluation, manufacturing control, and development. This test method quantitatively measures stress parameters that are used in a design or failure analysis that takes into account the effects of environmental exposure including that which occurs during processing, such as plating (8) (ASTM STP 962).5.2 For plating processes, the value of σth-IHE is used to specify quantitatively the maximum operating stress for a given structure or product.5.3 For quality control purposes, an accelerated test is devised that uses a specified loading rate, which is equal to or lower than the loading rate necessary to determine the threshold stress (see 8.1).5.4 For fasteners, the value of σth-IHE is used to specify quantitatively the maximum stress during installation and in service to avoid premature failure caused by residual hydrogen in the steel as a result of processing.5.5 For fasteners, the value of σth-EHE is used to specify quantitatively the maximum stress during installation and in service to avoid failure from hydrogen absorbed during exposure to a specific environment.5.6 To measure the relative susceptibility of steels to hydrogen pickup from various fabrication processes, a single, selected, discriminating rate is used to rank the resistance of various materials to hydrogen embrittlement.5.7 Annex A1 describes the application of this standard test method to hydrogen embrittlement testing of fasteners.1.1 This test method establishes a procedure to measure the susceptibility of steel to a time-delayed failure such as that caused by hydrogen. It does so by measuring the threshold for the onset of subcritical crack growth using standard fracture mechanics specimens, irregular-shaped specimens such as notched round bars, or actual product such as fasteners (2) (threaded or unthreaded) springs or components as identified in SAE J78, J81, and J1237.1.2 This test method is used to evaluate quantitatively:1.2.1 The relative susceptibility of steels of different composition or a steel with different heat treatments;1.2.2 The effect of residual hydrogen in the steel as a result of processing, such as melting, thermal mechanical working, surface treatments, coatings, and electroplating;1.2.3 The effect of hydrogen introduced into the steel caused by external environmental sources of hydrogen, such as fluids and cleaners maintenance chemicals, petrochemical products, and galvanic coupling in an aqueous environment.1.3 The test is performed either in air, to measure the effect if residual hydrogen is in the steel because of the processing (IHE), or in a controlled environment, to measure the effect of hydrogen introduced into the steel as a result of the external sources of hydrogen (EHE) as detailed in ASTM STP 543.1.4 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.NOTE 1: The values stated in metric units may not be exact equivalents. Conversion of the inch-pound units by appropriate conversion factors is required to obtain exact equivalence.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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