This specification covers two types and two grades of 2- and 3-wire, uncoated weldless steel and strand for use in pretensioned and posttensioned prestressed concrete construction. One specimen for test shall be taken from each production lot of finished strand and tested for breaking strength, yield strength and elongation. Strands of Grades 250 and 270 shall conform to specified breaking strength and yield strength requirements. Low relaxation strand shall also be tested as prescribed.1.1 This specification covers two types and two grades of 2-wire and 3-wire, uncoated steel strand for use in prestressed concrete construction. The two types of strand are low-relaxation and stress-relieved (normal-relaxation). Low-relaxation is to be regarded as the standard type. Stress-relieved (normal-relaxation) strand will not be furnished unless specifically ordered. The two grades are 250 [1725] and 270 [1860]. Grades 250 [1725] and 270 [1860] have minimum tensile strengths of 250 ksi [1725 MPa] and 270 ksi [1860 MPa] respectively, based on the nominal area of the strand.1.2 This specification is applicable for orders in either inch-pound units (as Specification A910) or in SI units (as Specification A910M).1.3 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not 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 specification.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.

定价： 515元 / 折扣价： 438 元 加购物车

4.1 This practice has been found to be very useful for preparing polyethylene samples suitable for determination of density by Test Method D1505, for quality control purposes, especially in a resin manufacturing facility where fast, reproducible, comparative results are needed. It is not necessarily recommended for resin specifications that are part of a sales contract between the buyer and the seller.4.2 The density of a polyethylene sample is highly dependent on the preparation and thermal history of the specimens. The level of density results obtained by this practice of sample preparation differs from that obtained by other methods as described in Practice D4703, Annex A1.4.3 Before proceeding with this practice, reference shall be made to the specification of the material being tested. Any test specimen preparation, conditioning, dimensions, or testing parameters, or some combination thereof, covered in the materials specification shall take precedence over those mentioned in this practice. If there are no material specifications, the default conditions apply.1.1 This practice covers the preparation of a sample for polyethylene density determination in accordance with Test Method D1505. The sample consists of a strand produced by extrusion of the polyethylene in accordance with Test Method D1238, Condition 190/2.16 (Melt Index).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 the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.NOTE 1: There is no known ISO equivalent to this standard.NOTE 2: The precision data on densities measured using this sample preparation practice is listed in Test Method D1505.1.4 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.

定价： 515元 / 折扣价： 438 元 加购物车

This guide covers standard specification for high-strength, extra-high-strength, and utilities grades of concentric lay steel wire strand composed of three wires or seven wires with Class A, Class B, or Class C zinc aluminum-mischmetal (Zn-5 Al-MM) alloy coatings specifically intended for use as overhead ground wires or static wires for electric power transmission lines. Alloy-coated steel wires, of varying sizes and grades of strand, shall conform to the specified values of the approximate weight per unit length of strand and the minimum breaking strength of the finished strand. The weight of the three classes of coating shall not be less than the specified value. The steel wires shall meet the required mechanical properties such as breaking strength, elongation, and ductility.1.1 This specification covers high-strength, extra-high-strength, and utilities grades of concentric lay steel wire strand composed of three wires or seven wires with Class A, Class B, or Class C zinc-5 % aluminum-mischmetal (Zn-5 Al-MM) alloy coatings specifically intended for use as overhead ground wires or static wires for electric power transmission lines.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.

定价： 515元 / 折扣价： 438 元 加购物车

This specification covers two sizes of extra-high-strength grade of concentric-lay steel wire strand, composed of seven, zinc-coated steel wires, specifically intended for use as the supporting messenger in Figure 8-type communication and electrical cables. Steel wires shall be manufactured by the open-hearth, basic-oxygen, or electric-furnace process. Materials shall adhere to specified mechanical and physical requirements such as breaking strength, elongation, ductility, nominal diameter, and coating weight and adherence. Zinc coatings shall be continuous and of reasonably uniform thickness, and wires shall be free from imperfections not consistent with good commercial practice.1.1 This specification covers two sizes of extra-high-strength grade of concentric-lay steel wire strand, composed of seven, zinc-coated steel wires, specifically intended for use as the supporting messenger in Figure 8-type communication and electrical cables.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 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.

定价： 515元 / 折扣价： 438 元 加购物车

4.1 Tension tests are generally to be performed on new wire ropes. The use of wire rope in any application can reduce individual wire strengths due to abrasion and nicking that will result in the wire rope strength being reduced. Damage to the outer wires will also lower the maximum strength achieved during tension testing.4.2 The modulus of elasticity of wire rope is not considered to be a standard requirement at this time. The determination of this material property requires specialized equipment and techniques.4.3 Rope to be tested should be thoroughly examined to verify that no external wire damage is present. If present, it should be noted. When possible, a new undamaged sample should be obtained for testing.4.4 End attachments and their installation can directly affect breaking force achieved during testing. Any attachment that can be used to directly achieve the required rope breaking force can be used. Standard testing with a poured socket, using zinc, white metal or thermoset resin, has been considered the most efficient. Proficiency in attachment of any fitting can have a direct effect on the final test results.1.1 This test method covers the tension testing of wire ropes and strand at room temperature, specifically to determine the measured breaking force, yield strength, elongation, and modulus of elasticity. Methods described in this standard are not intended for other purposes.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. Specific precautionary statements are given in Note 1 and Note 2.1.4 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.

定价： 515元 / 折扣价： 438 元 加购物车

4.1 The procedures described in this practice are intended to be used to establish design capacity (both strength and stiffness) values based on testing of OSB that, at a minimum, satisfies the relevant performance requirements of PS 2.4.2 Review and reassessment of values derived from this practice shall be conducted on a periodic basis. If a change is found to be significant, retesting or reevaluation, or both, in accordance with the procedures of this practice shall be considered.1.1 This practice covers the basis for code recognition of design capacities for OSB structural-use panels. Procedures are provided to establish or re-evaluate design capacities for OSB structural-use panels in flatwise and axial applications. Design capacities for OSB structural-use panels in edgewise applications, such as rim board, are outside the scope of this standard. Procedures for sampling and testing are also provided. Design values stated as capacity per unit dimension are to be regarded as standard. Design capacities developed in accordance with this practice are applicable to panels intended for use in dry in-service conditions.NOTE 1: This practice is based on ICC-ES Acceptance Criteria AC-182. Relative to the scope of AC-182, this practice is limited to OSB panels.NOTE 2: While this practice makes reference to PS 2, this practice applies similarly to products certified to other standards such as CAN/CSA O325.NOTE 3: OSB produced under PS 2 is rated with the “Exposure 1” bond classification. Exposure 1 panels covered by PS 2 are intended for dry use applications where the in-service equilibrium moisture content conditions are expected to be less than 16 %. Exposure 1 panels are intended to resist the effects of moisture due to construction delays, or other conditions of similar severity. Guidelines on use of OSB are available from manufacturers and qualified agencies.NOTE 4: PS 2-10 replaced the use of nominal thicknesses with a classification term known as Performance Category, which is defined in PS 2 as “A panel designation related to the panel thickness range that is linked to the nominal panel thickness designations used in the International Building Code (IBC) and International Residential Code (IRC).” Therefore, the PS 2 Performance Category should be considered equivalent to the term “nominal thickness” used within this standard.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 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.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 Seven-wire steel strand is used in pre-tensioned and post-tensioned concrete construction.4.2 0.600 in. [15.24 mm] diameter, Grade 270 seven-wire steel strand is used to make prestressed ground anchors which are often bonded to cement grout.4.3 Manufacturing processes, subsequent handling, and storage conditions may influence the strand bond.4.4 The primary use of this test method is to establish the relative bond strength of 0.600 in. [15.24 mm] seven-wire steel strand.4.5 The relative bond strength is determined by recording the pullout force at a certain displacement of the strand.AbstractThis test method deals with the standard procedures for establishing the relative bond strength of Grade 270 prestressing steel strands of specified diameter in cement grout as used in prestressed ground anchors for evaluating the effects of manufacturing practices on bond strength. The bond strength values obtained shall not be used to design the bond strength of ground anchors that depend on field conditions. This test method is not intended to be used as a bond test for pretensioned concrete applications. The test specimen shall be cut from standard production coils and shall not be wiped or cleaned. Pull test shall be made in accordance with the method.1.1 This test method describes procedures to establish the relative bond strength of 0.600 in. [15.24 mm] diameter, Grade 270 [1860] seven-wire steel strand in cement grout as used in prestressed ground anchors for the purpose of evaluating the effects of manufacturing practices on bond strength.1.2 The bond strength values obtained are not intended to be used to design the bond length of ground anchors that depend on field conditions.1.3 This test method is not intended to be used as a bond test for prestressed concrete applications.1.4 The values stated in either inch-pound or SI units are to be regarded as standard. Within the text, the SI units are shown in brackets. 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.

定价： 515元 / 折扣价： 438 元 加购物车

4.1 The breaking strength and elongation of the strand are determined by one or more tensile tests in which fracture of the specimen ideally occurs in the free span.4.2 Mechanical properties of the strand will be negatively affected if proper care is not taken to prevent damage such as severe bending, abrasion, or nicking of the strand during sampling.4.3 Premature failure of the test specimens may result if there is appreciable notching, cutting, or bending of the specimen by the gripping devices of the testing machine.4.4 Errors in testing will result if the wires constituting the strand are not loaded uniformly.4.5 The mechanical properties of the strand will be materially affected by excessive heating during test specimen collection or preparation.1.1 These test methods describe procedures for testing the mechanical properties of multi-wire steel prestressing strand.1.2 These test methods are intended for use in evaluating specific strand properties prescribed in specifications for multi-wire steel prestressing strand, but they do not quantify acceptance criteria specified in the applicable specification for the strand being tested.1.3 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.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.

定价： 590元 / 折扣价： 502 元 加购物车

This specification covers copper-clad steel wire strand composed of a number of round steel, copper-clad wires, for use as guys, messengers, span wires, and for similar purposes where electrical conductance is not a requirement. The strand is classified based on the minimum breaking strength and number of wires in the strand. Each wire in the strand shall be composed of a steel core made from steel produced by commercially-accepted steel-making process, with a substantially uniform and continuous copper cladding thoroughly bonded to it throughout. Each wire in the strand shall be of such quality that, when drawn to a specified size and when fabricated into strand, the finished copper-clad steel wire strand shall have the prescribed properties and characteristics. Strands of varying minimum breaking strength shall conform to the prescribed package size of coils or reels. The minimum thickness of the copper cladding on wires taken from the finished strand shall not be less than the specified values. Mechanical properties like breaking strength and elongation shall be determined. Torsion test and wrap test shall also be conducted on the test specimens.1.1 This specification covers copper-clad steel wire strand composed of a number of round steel, copper-clad wires, for use as guys, messengers, span wires, and for similar purposes where electrical conductance is not a requirement.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 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.

定价： 515元 / 折扣价： 438 元 加购物车

This specification deals with the standard types and grade requirements of seven-wire, uncoated steel strands for use in the construction of pre-tensioned and post-tensioned pre-stressed concrete. The two types of strand are low-relaxation and stress-relieved (normal relaxation). The base metal shall be made of carbon steel and shall undergo stranding and continuous thermal and mechanical treatment. Mechanical testing methods shall be performed to determine the breaking strength, yield strength, elongation, and stress relaxation properties wherein the strand shall conform to the required mechanical attributes of the product. Final products shall be furnished on reels or in reelless packs for packaging and marked with two strong tags for identification. The requirements specified herein shall also be applicable for pre-stressed ground anchor construction.1.1 This specification covers two grades of low-relaxation, seven-wire steel strand for use in prestressed concrete construction. Grade 250 [1725] and Grade 270 [1860] have minimum tensile strengths of 250 ksi [1725 MPa] and 270 ksi [1860 MPa], respectively, based on the nominal area of the strand.1.2 A supplementary requirement (S1) is provided for use where bond strength testing of 0.600-in. [15.24-mm] diameter Grade 270 [1860] strand for applications in prestressed ground anchors is required by the purchaser. The supplementary requirement applies only when specified in the purchase order.1.3 The text of this specification contains notes or footnotes, or both, that provide explanatory material. Such notes and footnotes do not contain any mandatory information.1.4 This specification is applicable for orders in either inch-pound units (as Specification A416) or in SI units (as Specification A416M).1.5 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. 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 specification.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.

定价： 590元 / 折扣价： 502 元 加购物车

This specification covers high strength, extra-high-strength, and utilities grades of concentric lay steel wire strand composed of three wires or seven wires in class A, class B, or class C zinc coatings specifically intended for use as overhead ground wires or static wires for electric transmission lines. The strand shall have a left lay with a uniform pitch of not more than 16 times the nominal diameter of the strand. The strand is preformed when the component wires are set to the helical form which they assume in the product by any means of process other than by merely laying them about the strand core. The approximate weight per unit length of strand and the minimum breaking strength of the finished strand are presented. The elongation shall be measured as the percentage increase in separation between the jaws of the testing machine from the position after application of the initial load, to the position of at initial failure in the test specimen.1.1 This specification covers high-strength, extra-high-strength, and utilities grades of concentric lay steel wire strand composed of three wires or seven wires with Class A, Class B, or Class C zinc coatings specifically intended for use as overhead ground wires or static wires for electric power transmission lines.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 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.

定价： 515元 / 折扣价： 438 元 加购物车

This specification covers the standard for stainless steel wire strand composed of a multiplicity of round wires and suitable for use as guy wires, overhead ground wires, and similar purposes. Stranding shall be sufficiently close to ensure no appreciable reduction in diameter when stressed to the specified strength. Several types of steel are covered like Type 302, 304, 305, 316, 316Cb, or 316Ti and shall conform to the required chemical composition values in carbon, manganese, phosphorus, sulfur, silicon, chromium, nickel, molybdenum, and nitrogen. The tensile strength, based upon the nominal strand diameter and the number of wires in each strand, shall conform to the minimum values in breaking strength. The individual wires of the completed strand shall not fracture when wrapped in a close helix of at least two turns upon itself as a mandrel.1.1 This specification covers stainless steel wire strand composed of a multiplicity of round wires and suitable for use as guy wires, overhead ground wires, and similar purposes.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 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.

定价： 515元 / 折扣价： 438 元 加购物车

This specification covers seven-wire, uncoated, compacted, stress-relieved steel strand for prestressed concrete. The chemical requirements, mechanical requirements, and dimensions and permissible variations are presented. The mechanical requirement includes breaking strength, load at 1% extension and elongation. Different test method shall be performed on the strand that includes dimension test, breaking strength test, load at 1% extension test, elongation test and workmanship.1.1 This specification covers two types and three grades of compacted, seven-wire, uncoated strand for use in prestressed concrete construction. The two types of strand are low-relaxation and stress-relieved (normal-relaxation). The three grades are 245 [1700], 260 [1800] and 270 [1860].1.2 This specification is applicable for orders in either inch-pound units (as Specification A779) or in SI units (as Specification A779M).1.3 The values stated in either inch-pound or SI units are to be regarded as standard. Within the text, the SI units are shown in brackets. 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 specification.

定价： 515元 / 折扣价： 438 元 加购物车

5.1 Acceptance Testing—Option A1 of Test Method D2256 is considered satisfactory for acceptance testing of commercial shipments because the test method has been used extensively in the trade for acceptance testing. However, this statement is not applicable to knot and loop breaking force tests, tests on wet specimens, tests on oven-dried specimens, or tests on specimens exposed to low or high temperatures and should be used with caution for acceptance testing because factual information on between-laboratory precision and bias is not available.5.1.1 If there are differences of practical significance between reported test results for two laboratories (or more), comparative tests should be performed to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, use the samples for such a comparative tests that are as homogeneous as possible, drawn from the same lot of material as the samples that resulted in disparate results during initial testing and randomly assigned in equal numbers to each laboratory. The test results from the laboratories involved should be compared using a statistical test for unpaired data, a probability level chosen prior to the testing series. If a bias is found, either its cause must be found and corrected, or future test results for that material must be adjusted in consideration of the known bias.5.2 Fundamental Properties—The breaking tenacity, calculated from the breaking force and the linear density, and the elongation are fundamental properties that are widely used to establish limitations on yarn processing or conversion and on their end-use applications. Initial modulus is a measure of the resistance of the yarn to extension at forces below the yield point. The chord modulus is used to estimate the resistance to imposed strain. The breaking toughness is a measure of the work necessary to break the yarn.5.3 Comparison to Skein Testing—The single-strand method gives a more accurate measure of breaking force present in the material than does the skein method and uses less material. The skein-breaking force is always lower than the sum of the breaking forces of the same number of ends broken individually.5.4 Applicability—Most yarns can be tested by this test method. Some modification of clamping techniques may be necessary for a given yarn depending upon its structure and composition. To prevent slippage in the clamps or damage as a result of being gripped in the clamps, special clamping adaptations may be necessary with high modulus yarns made from fibers such as glass or extended chain polyolefin. Specimen clamping may be modified as required at the discretion of the individual laboratory providing a representative force-elongation curve is obtained. In any event, the procedure described in this test method for obtaining tensile properties must be maintained.5.5 Breaking Strength—The breaking strength of a yarn influences the breaking strength of fabrics made from the yarn, although the breaking strength of a fabric also depends on its construction and may be affected by manufacturing operations.5.5.1 Because breaking strength for any fiber-type is approximately proportional to linear density, strands of different sizes can be compared by converting the observed breaking strength to breaking tenacity (centinewtons per tex, grams-force per tex, or grams-force per denier).5.6 Elongation—The elongation of a yarn has an influence on the manufacturing process and the products made. It provides an indication of the likely stretch behavior of garment areas such as knees, elbows, or other points of stress. It also provides design criteria for stretch behavior of yarns or cords used as reinforcement for items such as plastic products, hose, and tires.5.7 Force-Elongation Curve—Force-elongation curves permit the calculation of various values, not all of which are discussed in this test method, such as elongation at break, elongation at specified force, force at specified elongation, initial elastic modulus which is resistance to stretching, compliance which is ability to yield under stress, and is the reciprocal of the elastic modulus, and area under the curve, a measure of toughness, which is proportional to the work done.NOTE 3: Force-elongation curves can be converted to stress-strain curves if the force is converted to unit stress, such as to centinewtons per tex, or pounds per square inch, or pascals, or grams-force per tex, or grams-force per denier, and the elongation is based on change per unit length.5.8 Knot and Loop Breaking Force—The reduction in breaking force due to the presence of a knot or loop is considered a measure of the brittleness of the yarn. Elongation in knot or loop tests is not known to have any significance and is not usually reported.5.9 Rate of Operation—In general, the breaking force decreases slightly as time-to-break increases.5.9.1 Operation of CRT, CRE, and CRL tension testing machines at a constant time-to-break has been found to minimize differences in test results between the three types of tension testing machines. When tensile tests are performed at a fixed time-to-break, then reasonable agreement in breaking force has generally been found to exist between CRT and CRE tension testing machines.4 Consistent results are also obtained between different manufacturers of CRL tension testing machines when they are operated at the same time-to-break. The agreement is not necessarily good, however, between CRE or CRT tension testing machines on the one hand and CRL tension testing machines on the other even when they are all operated at the same time-to-break. The CRE-type tester is the preferred tension testing machine.5.9.2 This test method specifies an average time-to-break of 20 ± 3 s as recommended by Specification D76/D76M. It also provides for alternate speeds, such as 300 ± 10 mm [12 ± 0.5 in.]/min when using a 250-mm [10-in.] gauge length. See 9.2.5.9.3 The tolerance of ±3 s for the time-to-break is wide enough to permit convenient adjustment of the tension testing machine's rate of operation, and it is narrow enough to ensure good agreement between tests. The difference in breaking force between tests at 17 and 23 s will usually not exceed 1.5 % of the higher value.5.9.4 In case a tension testing machine is not capable of being operated at 20-s time-to-break, alternative rates of operation are included in this test method. These alternative rates may be used only by agreement between the parties concerned or when required in an applicable material specification.5.10 Tests on Wet Specimens—Tests on wet specimens are usually made only on yarns which show a loss of breaking force when wet or when exposed to high humidity, for example, yarns made from animal fibers and man-made fibers based on regenerated and modified cellulose. Wet tests are made on flax yarns to detect adulteration by failure to show a gain in breaking force.5.11 Tests on Oven-Dried Specimens and Specimens at High Temperatures—Tests on oven-dried specimens at standard or high temperatures are usually made only on yarns that will be used at high temperatures or will be used under very dry conditions which will affect the observed breaking force, for example, on rayon yarns intended for use in tire cords and yarns for other industrial purposes. Note that results obtained when testing oven-dried specimens at standard temperature will not necessarily agree with the results obtained when testing oven-dried yarns at high temperatures.5.12 Tests on Specimens at Low Temperatures—Tests on specimens exposed to low temperatures are usually made only on yarns that will be used at low temperatures, for example, yarns used in outerwear designed for cold climates or outer-space situations. Low-temperature tests are made on coated yarns used in the manufacture of materials used in outdoor applications, such as screening fabrics.1.1 This test method covers the determination of tensile properties of monofilament, multifilament, and spun yarns, either single, plied, or cabled with the exception of yarns that stretch more than 5.0 % when tension is increased from 0.05 to 1.0 cN/tex [0.5 to 1.0 gf/tex].1.2 This test method covers the measurement of breaking force and elongation of yarns and includes directions for the calculation of breaking tenacity, initial modulus, chord modulus, and breaking toughness.1.2.1 Options are included for the testing of specimens in: (A) straight, (B) knotted, and (C) looped form.1.2.2 Conditions of test are included for the testing of specimens that are: (1) conditioned air, (2) wet, not immersed, (3) wet, immersed, (4) oven-dried, (5) exposed to elevated temperature, or (6) exposed to low temperature.NOTE 1: Special methods for testing yarns made from specific fibers; namely, glass, flax, hemp, ramie, and kraft paper and for specific products; namely, tire cords and rope, have been published: Test Methods D885, and Specification D578.NOTE 2: For directions covering the determination of breaking force of yarn by the skein method refer to Test Method D1578.1.3 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.1.4 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.

定价： 646元 / 折扣价： 550 元 加购物车

5.1 Prestressing steel strand is used in pre-tensioned and post-tensioned concrete construction.5.2 In pre-tensioned concrete applications, the prestressing steel strand is expected to transfer prestressing forces to the structural member by means of the adhesion (that is, bond) of the exposed wire strand surfaces to the surrounding cementitous material.5.3 Manufacturing processes, subsequent handling, and storage conditions can influence the strand bond.5.4 Prestressing steel strand is used in construction applications with a variety of concrete mixtures. Developing tests and threshold values for the performance of the strand in each of these unique mixtures is impractical.1.1 This test method describes procedures for determining the bond of seven-wire steel prestressing strand. The bond determined by this test method is stated as the tensile force required to pull the strand through the cured mortar in a cylindrical steel casing. The result of the test is the tensile force measured on the loaded-end of the strand corresponding to a movement of 0.1 in. [2.5 mm] at the free-end of the strand.1.2 This test method is applicable either in inch-pound units (as Test Method A1081) or SI units (as Test Method A1081M).1.3 The values stated in either inch-pound units or in SI units are to be regarded separately as standard. Within the text, SI units are shown in brackets. 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 test method.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.

定价： 590元 / 折扣价： 502 元 加购物车