定价： 515元 加购物车

5.1 This test method may be used for determining compliance with a specification for maximum cashmere coarse-hair content and is required to be used for determining compliance with Specification D2817.5.1.1 In case of a dispute arising from differences in reported test results when using Test Method D2816 for acceptance testing of commercial shipments, the purchaser and the supplier should conduct comparative tests to determine if there is a statistical bias between their laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of test specimens that are as homogeneous as possible and that are from a lot of material of the type in question. The test specimens should then be randomly assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using Student's t-test for unpaired data and an acceptable probability level chosen by the two parties before the testing is begun. If a bias is found, either its cause must be found and corrected or the purchaser and the supplier must agree to interpret future test results in the light of the known bias.5.2 When the product being tested has a cashmere coarse-hair content that departs significantly either way from the specified amount, the sequential test procedure described herein will result in a substantial reduction in the number of observations required for a decision at the stated level of confidence. On the other hand, when the product being tested has a cashmere coarse-hair content that approaches the specified amount, the sequential procedure ensures that the necessary increased number of observations shall be made to secure a correct decision at the stated level of confidence.1.1 This test method covers a sequential procedure for determining whether or not the cashmere coarse-hair content of a sample exceeds a specified value.NOTE 1: For the maximum allowable cashmere coarse-hair content in cashmere, refer to Specification D2817.NOTE 2: For the quantitative analysis of cashmere hair and blends of cashmere hair and other fibers, refer to Test Methods D629.1.2 This test method is applicable only to cashmere hair in the form of roving, yarn, or fabric, and to the cashmere hair content of blends with other fibers, where the expected cashmere coarse-hair content is not more than five mass percent (see Footnote C of Table 1). For greater expected mass percentages of cashmere coarse-hair, see Test Methods D629.The data from these studies are on file with the Secretary of Subcommittee D13.13, Committee D13 of ASTM.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 加购物车

4.1 This specification sets the maximum permissible cashmere coarse-hair content for cashmere in the form of roving, yarn, or fabric.4.2 When agreed upon by parties in interest, this specification provides a basis for acceptance testing of roving, yarn, or fabric of cashmere, or blends of cashmere and other fibers in such products.AbstractThis specification sets the maximum permissible cashmere coarse-hair content in cashmere in the form of roving, yarn, or fabric. Single standard testing for the determination of the cashmere coarse-hair content shall be enough. In case of dispute, additional tests may be done.1.1 This specification covers the allowable cashmere coarse-hair content in cashmere which has been processed at least to the roving stage.1.2 For blends of cashmere hair and other fibers, this specification is applicable only to the cashmere hair content of such blends.NOTE 1: For the determination of the cashmere coarse-hair content in cashmere, refer to Test Method D2816. For the identification of textile fibers see Methods D276. For the quantitative determination of the composition of textile blends, see Test Methods D629.1.3 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 加购物车

4.1 Some specifications contain requirements relating to percentage of fractured particles in coarse aggregates. One purpose of such requirements is to maximize shear strength by increasing inter-particle friction in either bound or unbound aggregate mixtures. Another purpose is to provide stability for surface treatment aggregates and to provide increased friction and texture for aggregates used in pavement surface courses. This test method provides a standard procedure for determining the acceptability of coarse aggregate with respect to such requirements.4.2 Specifications differ as to the number of fractured faces required on a fractured particle, and they also differ as to whether percentage by mass or percentage by particle count shall be used. If the specification does not specify, use the criterion of at least one fractured face and calculate percentage by mass.1.1 This test method covers the determination of the percentage, by mass or by count, of a coarse aggregate sample that consists of fractured particles meeting specified requirements.1.2 The values stated in SI units are to be regarded as the standard. The values in parentheses are provided 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.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： 590元 加购物车

5.1 These test methods are used to measure one-dimensional vertical flow of water through initially saturated coarse-grained, pervious (that is, free-draining) soils under an applied hydraulic gradient. Hydraulic conductivity of coarse-grained soils is used in various civil engineering applications. These test methods are suitable for determination of hydraulic conductivity for soils with k > 10–7 m/s.NOTE 2: Clean coarse-grained soils that are classified using Practice D2487-17 as GP, GW, SP, and SW can be tested using these test methods. Depending on fraction and characteristics of fine-grained particles present in soils, these test methods may be suitable for testing other soil types with fines content greater than 5 % (for example, GP-GC, SP-SM).5.2 Coarse-grained soils are to be tested at a void ratio representative of field conditions. For engineered fills, compaction specification can be used to provide target test conditions, whereas for natural soils, field testing of in-situ density can be used to provide target test conditions.5.3 Use of a dual-ring permeameter is included in these test methods in addition to a single-ring permeameter for the rigid wall test apparatus. The dual-ring permeameter allows for reducing potential adverse effects of sidewall leakage on measured hydraulic conductivity of the test specimens. The use of a plate at the outflow end of the specimen that contains a ring with a diameter smaller than the diameter of the permeameter and the presence of two outflow ports (one from the inner ring, one from the annular space between the inner ring and the permeameter wall) allows for separating the flow from the central region of the test specimen from the flow near the sidewall of the permeameter.NOTE 3: Sidewall leakage has been reported to have significant influence on flow conditions for coarse-grained soils due to presence of larger voids at the boundary and higher void ratio in this region of the specimen. Three modifications that have been used to reduce this effect in rigid wall permeameters include: i) placing a piping barrier (for example, caulk rings along every approximately 25-mm length of sidewall), ii) spreading a layer of bentonite and petroleum jelly mixture along the entire surface area of the sidewall, and iii) using a closed-cell neoprene liner attached to the inside wall of the permeameter.5.4 Use of a flexible wall permeameter is included in these test methods in addition to the rigid wall permeameters. The flexible wall permeameter reduces potential adverse effects of sidewall leakage on measured hydraulic conductivity of the test specimens and allows for application of hydrostatic confining stress conditions on the specimen during the hydraulic conductivity test. Confining stress allows for representing field conditions (that is, simulating stress states in the subgrade that may affect values of k).5.5 Darcy's law is assumed to apply to the test conditions, flow is assumed to be laminar (see Note 4), and the hydraulic conductivity is assumed to be considered independent of hydraulic gradient. The validity of these assumptions may be evaluated by measuring the hydraulic conductivity of a specimen at three different hydraulic gradients. The discharge velocity (v = k × i) is plotted against the applied hydraulic gradient. If the resulting relationship is linear and the measured hydraulic conductivity values are similar (that is, within 25 %), then these assumptions are considered valid.NOTE 4: Previous studies suggest that the limit between turbulent flow and laminar flow for soils occurs for Reynolds numbers between 1 and 10 (1 and 2)3. A formulation for Reynolds number (and division for laminar and turbulent flow conditions) for flow through packed beds has been reported (3). The formulation is presented for uniformly graded, spherical particles in Eq 1.where:Re*   =   Reynolds Number for packed bed flow,D   =   granule or particle diameter (m),v   =   superficial fluid velocity (that is, Darcy velocity) through bed (m/s),ρf   =   fluid density (kg/m3),μ   =   liquid viscosity (dynamic viscosity) (Pa s), andn   =   porosity of bed (expressed as a ratio).Provisions are provided in (3) for establishing equivalent particle diameter for use in this equation for nonuniform particle size distributions and nonspherical particles.NOTE 5: Using sufficiently low gradients has been demonstrated to be important for obtaining representative results. Hydraulic gradients less than 0.05 have been reported (4). Using a long test specimen (on the order of 1.5 m) has been reported as an effective method for achieving appropriately low hydraulic gradients for materials with k > 0.01 m/s.NOTE 6: The quality of the result produced by this standard is dependent of the competence of the personnel performing it and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself result in reliable values. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.AbstractThis test method covers the determination of the coefficient of permeability by a constant-head method for the laminar flow of water through granular soils. The procedure is to establish representative values of the coefficient of permeability of granular soils that may occur in natural deposits as placed in embankments, or when used as base courses under pavements. The different apparatus used in determining the granular soil permeability are presented. The methods in preparing the test specimen are presented in details. The testing and calculation procedure for granular soil permeability determination are presented.1.1 These test methods cover laboratory measurement of the hydraulic conductivity (also referred to as coefficient of permeability) of water-saturated coarse-grained soils (for example, sands and gravels) with k > 10–7 m/s. The test methods utilize low hydraulic gradient conditions.1.2 This standard describes two methods (A and B) for determining hydraulic conductivity of coarse-grained soils. Method A incorporates use of a rigid wall permeameter and Method B incorporates the use of a flexible wall permeameter. A single- or dual-ring rigid wall permeameter may be used in Method A. A dual-ring permeameter may be preferred over a single-ring permeameter when adverse effects from short-circuiting of permeant water along the sidewalls of the permeameter (that is, prevent sidewall leakage) are suspected by the user of this standard.1.3 The test methods are used under constant head conditions.1.4 The test methods are used under saturated soil conditions.1.5 Water is used to permeate the test specimen with these test methods.1.6 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.NOTE 1: Hydraulic conductivity has traditionally been reported in cm/s in the US, even though the official SI unit for hydraulic conductivity is m/s.1.7 The observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 646元 加购物车

定价： 712元 加购物车

定价： 0元 / 折扣价： 0 元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

定价： 590元 加购物车

5.1 The Micro-Deval abrasion test is a test of coarse aggregate to determine abrasion loss in the presence of water and an abrasive charge. Many aggregates are more susceptible to abrasion when wet than dry, and the use of water in this test incorporates this reduction in resistance to degradation in contrast to some other tests, which are conducted on dry aggregate. The test results are helpful in evaluating the toughness/abrasion resistance of coarse aggregate subject to abrasion when adequate information is not available from service records.5.2 The Micro-Deval abrasion test is useful for detecting changes in properties of aggregate produced from an aggregate source as part of a quality control or quality assurance process.1.1 This test method covers a procedure for testing coarse aggregate for resistance to abrasion using the Micro-Deval apparatus.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 The text of this method 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 test method.1.4 This procedure may involve hazardous materials, operations, and equipment. 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.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 加购物车

定价： 590元 加购物车

5.1 The particle shape of coarse aggregates influences the properties of some construction materials and may affect their placement and consolidation.5.2 This test method provides a means for checking compliance with specifications that limit such particles or to determine the relative shape characteristics of coarse aggregates.1.1 This test method covers the determination of the percentages of flat particles, elongated particles, or flat and elongated particles in coarse aggregates. Two procedures, Method A and Method B, are presented in this standard. Method A is a reflection of the original procedure as developed prior to Superpave and is intended for all non-Superpave applications. Method B is a comparison of the maximum particle dimension to the minimum particle dimension and is intended for use with Superpave specifications.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.1.2.1 Exception (regarding sieves, per Specification E11)—The values stated in SI units shall be considered standard for the dimensions of the wire cloth openings and the diameter of the wires used in the wire cloth. When sieve mesh sizes are referenced, the alternate inch-pound designations are provided for information purposes and enclosed in parentheses.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： 590元 加购物车

定价： 590元 加购物车

This specification covers the general requirements for carbon steel wire rods and uncoated coarse round wire in coils or straightened and cut lengths. Chemical compositions are specified by ranges or limits for carbon and other elements. The grades commonly specified for carbon steel wire rods and coarse round wire are presented. Grain size, when specified, and the mechanical properties enumerated in individual specifications shall be determined in accordance with reference test materials.1.1 This specification covers general requirements for carbon and alloy steel wire rods and uncoated coarse round wire in coils or straightened and cut lengths.1.2 In case of conflict, the requirements in the purchase order, on the drawing, in the individual specification, and in this general specification shall prevail in the sequence named.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. Within the text, inch-pound units are shown in brackets.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： 590元 加购物车

定价： 156元 / 折扣价： 133 元 加购物车