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定价： 156元 / 折扣价： 133 元 加购物车

4.1 From the light ship characteristics one is able to calculate the stability characteristics of the vessel for all conditions of loading and thereby determine whether the vessel satisfies the applicable stability criteria. Accurate results from a stability test may in some cases determine the future survival of the vessel and its crew, so the accuracy with which the test is conducted cannot be overemphasized. The condition of the vessel and the environment during the test is rarely ideal and consequently, the stability test is infrequently conducted exactly as planned. If the vessel is not 100 % complete and the weather is not perfect, there ends up being water or shipyard trash in a tank that was supposed to be clean and dry and so forth, then the person in charge must make immediate decisions as to the acceptability of variances from the plan. A complete understanding of the principles behind the stability test and a knowledge of the factors that affect the results is necessary.1.1 This guide covers the determination of a vessel’s light ship characteristics. In this standard, a vessel is a traditional hull-formed vessel. The stability test can be considered to be two separate tasks; the lightweight survey and the inclining experiment. The stability test is required for most vessels upon their completion and after major conversions. It is normally conducted inshore in calm weather conditions and usually requires the vessel be taken out of service to prepare for and conduct the stability test. The three light ship characteristics determined from the stability test for conventional (symmetrical) ships are displacement (“displ”), longitudinal center of gravity (“LCG”), and the vertical center of gravity (“KG”). The transverse center of gravity (“TCG”) may also be determined for mobile offshore drilling units (MODUs) and other vessels which are asymmetrical about the centerline or whose internal arrangement or outfitting is such that an inherent list may develop from off-center weight. Because of their nature, other special considerations not specifically addressed in this guide may be necessary for some MODUs. This standard is not applicable to vessels such as a tension-leg platforms, semi-submersibles, rigid hull inflatable boats, and so on.1.2 The limitations of 1 % trim or 4 % heel and so on apply if one is using the traditional pre-defined hydrostatic characteristics. This is due to the drastic change of waterplane area. If one is calculating hydrostatic characteristics at each move, such as utilizing a computer program, then the limitations are not applicable.1.3 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.1.3.1 Exceptions—Other units may be used for the stability test, but the test results should be reported in the same units and coordinate system as the vessel’s draft marks and Trim and Stability Book or similar stability information provided.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： 843元 / 折扣价： 717 元 加购物车

5.1 The measured or calculated equilibrium density of structural lightweight concrete determines whether specified density requirements have been met. Unless otherwise specified, determine equilibrium density by calculation using the procedures in 9.2.5.2 Test Method C138/C138M shall be used to determine the density of freshly mixed lightweight concrete for compliance with concrete placement specifications.NOTE 1: The fresh density of lightweight aggregate concrete is a function of mixture proportions, air content, water demand, and the specific density and moisture content of the lightweight aggregate. Decrease in density of a specific lightweight concrete is due to moisture loss that, in turn, is a function of aggregate moisture content, ambient conditions, and the ratio of the surface area to the volume of the concrete member. For most structural lightweight concretes, equilibrium density is approached at about 90 days. For most high-strength lightweight concretes, equilibrium density is approached at about 180 days. Extensive tests demonstrate that despite variations in the initial moisture content of lightweight aggregate, the equilibrium density will be approximately 50 kg/m3 [3.0 lb/ft3] greater than the oven-dry density.1.1 This test method provides procedures to determine the oven-dry and equilibrium densities of structural lightweight concrete.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. Some values have only SI units because the inch-pound equivalents are not used in practice.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

5.1 The g-max values obtained by these procedures are indicative of the impact attenuation characteristics of playing surfaces used for sports such as American football, soccer, baseball, lacrosse, rugby, etc. Optional time history data can be used to further describe these properties.1.1 This test method is used to determine the impact-attenuation characteristics of natural turfgrass and soil playing surface systems with a lightweight portable apparatus. This test method can be used to compare the impact attenuation characteristics of natural playing surface systems, as well as assessing the effects of management practices on the impact attenuation characteristics. This test method also can be used to assess the compactibility of natural playing surfaces by recording g-max values or penetration of successive impacts, or both.1.2 This test method provides a procedure for assessing impact attenuation characteristics in the field, on both actual playing surfaces and research plots. Numerical data will not be comparable to data obtained using a different missile mass or geometry, different drop height, or different standard method, for example, Test Method F1936.1.3 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, 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

1.1 This specification establishes the standard practice for the maintenance and continued airworthiness of a lightweight unmanned aircraft system (UAS).1.2 At a minimum, a UAS is defined as a system composed of the unmanned aircraft and all required subsystems, control station, all required crew members, command and control (C2) links, and any required launch and recovery equipment.1.3 The intended use for this specification is for civil aviation authority (CAA), self-, or third-party determinations of continued airworthiness for UAS. This specification provides the core requirements for continued airworthiness of lightweight UAS or for certain CAA operational approvals using risk-based categories, or both. Additional requirements are envisioned to address the requirements for expanded operations and characteristics not addressed by this specification.1.4 This specification is intended to support aircraft developed in accordance with Specifications F2910, F3002, F3005, and F3298.1.5 This specification is intended to support UAS operations. It is assumed that the risk of UAS will vary based on concept of operations, environment, and other variables. The fact that there are no human beings onboard the UAS may reduce or eliminate some hazards and risks.1.6 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.1.7 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 This test method evaluates the potential degree of staining attributable to the presence of iron compounds in a lightweight aggregate sample primarily by means of a visual classification method. Such compounds may or may not produce stains on the surface of the concrete in which the aggregate is incorporated.1.1 This test method covers the testing of lightweight concrete aggregates to evaluate the potential degree of staining from iron compounds.1.2 The values stated in SI units are to be regarded as the standard. The inch-pound values given 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： 515元 / 折扣价： 438 元 加购物车

1.1 This document covers two types of lightweight electrical equipment shelters designed for transport on both the M1037 and M1097 High Mobility Multipurpose Wheeled Vehicle (HMMWV). These shelters are transported by rail, air, marine and highway when mounted or dismounted from their vehicles.1.2 Classification—The shelters will be of the following types, as specified (see ).1.2.1 Type I—Shelter, Electrical Equipment, Lightweight (w/o Tunnel, 17-2-0035-1).1.2.2 Type III—Shelter, Electrical Equipment, Lightweight, Modified, General Purpose (w/Tunnel, 17-2-0035-3).1.3 The values stated in inch-pound units are to be regarded as the standard. The values given in parenthesis are for information only.1.4 The following safety hazards caveat pertains only to the test required portion, Section 4, of this specification: 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 requirements prior to use.1.5 Provisional standards achieve limited consensus through approval of the sponsoring committee.

定价： 0元 / 折扣价： 0 元

1.1 This specification covers lightweight aggregate intended to provide water for internal curing of concrete. It includes test methods for determining the absorption and desorption properties of lightweight aggregate.NOTE 1: Internal curing provides an additional source of water to sustain hydration and substantially reduce the early-age autogenous shrinkage and self-desiccation that can be significant contributors to early-age cracking. Appendix X1 provides guidance on calculating the quantity of lightweight aggregate for internal curing.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. Some values have only SI units because the inch-pound equivalents are not used in practice.NOTE 2: Sieve size is identified by its standard designation in Specification E11. The alternative designation given in parentheses is for information only and does not represent a different standard sieve size.1.3 The text of this specification references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of 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： 590元 / 折扣价： 502 元 加购物车

Many of the benefits of walls with high sound transmission class ratings (STC), can be lost because of poor construction details or improper installation. Established reputable manufacturers of building materials and systems exercise great care to properly determine the acoustical performance of their products and, specifically, the ability of wall systems to attenuate sound. The laboratory-measured performance of partitions will not be achieved in buildings unless both the construction details of the acoustically rated wall and the installation details such as described in this procedure are strictly followed. This practice is intended to emphasize several factors that can substantially reduce the sound insulation of an otherwise good wall and to illustrate satisfactory solutions. The STC rating of the partition alone does not necessarily determine the acoustic privacy of the total construction. Note 1—Adherence to the precautions described in this recommended practice for control of sound leaks and flanking transmission should help achieve the noise reduction anticipated by laboratory tests. However, it is cautioned that the control of workmanship, materials, and site conditions is not as simple as it is in a laboratory.1.1 This practice covers measures intended to prevent situations or conditions that will detract from the sound-insulating properties of acoustically-rated lightweight partitions. It is not intended to include all sound insulating constructions. Many acoustically-rated partitions are also fire rated and when being installed must be built in accordance with the construction details specified in the fire test construction. In any event, applicable building codes and regulations should be checked for possible conflicts. 1.2 Excluded from this scope are masonry type partitions having all or part of their construction from brick, concrete block, aggregate block, plaster block, poured concrete, etc. Also excluded are operable and demountable partitions (Operable are those partitions with a mechanism for easy movement; demountable partitions are those which are designed and installed with the intent of later being taken down and re-erected by a crew over a period of time, with the components being reusable). Not excluded are those partitions which are lightweight but have thin brick, tile, or plaster on one or both faces. 1.3 Plumbing wall and kitchen problems are excluded from this document. 1.4 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only. 1.5 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems 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.

定价： 0元 / 折扣价： 0 元

This specification covers lightweight aggregates intended for use in structural concrete in which prime considerations are reducing the density while maintaining the compressive strength of the concrete. Procedures covered in this specification are not intended for job control of concrete. Two general types of lightweight aggregates are covered by this specification: aggregates prepared by expanding, pelletizing, or sintering products such as blast-furnace slag, clay, diatomite, fly ash, shale, or slate; and aggregates prepared by processing natural materials, such as pumice, scoria, or tuff. The aggregates shall be composed predominately of lightweight-cellular and granular inorganic material. Lightweight aggregates shall be tested, and should not contain excessive amounts of deleterious substances; and should conform to the specified values of organic impurities, aggregate staining, aggregate loss of ignition, clay lumps and friable particles, loose bulk density, compressive strength, drying shrinkage, popouts, and resistance to freezing and thawing.1.1 This specification covers lightweight aggregates intended for use in structural concrete in which prime considerations are reducing the density while maintaining the compressive strength of the concrete. Procedures covered in this specification are not intended for job control of concrete.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 With regard to other units of measure, the values stated in inch-pound units are to be regarded as standard.1.3 The text of this specification 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.NOTE 1: This specification is regarded as adequate to ensure satisfactory lightweight aggregates for most concrete. It is recognized that it may be either more or less restrictive than needed for some conditions and for special purposes, such as fire resistance, fill, and concrete constructions, the use of which is based on load tests rather than conventional design procedures.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 lightweight aggregates intended for use in concrete masonry units when a prime consideration is to reduce the density of the units. Three general types of lightweight aggregates are covered by this specification: aggregates prepared by expanding, palletizing, or sintering products such as blast-furnace slag, clay, diatomite, fly ash, shale, or slate; aggregates prepared by processing natural materials such as pumice, scoria, or tuff; and aggregates consisting of end products of coal or coke combustion. The aggregates shall be composed predominately of lightweight-cellular and granular inorganic material. The aggregates shall not contain excessive amounts of deleterious substances, as determined by organic impurities, staining, and loss on ignition tests. Lightweight aggregate under test shall meet requirements for clay lumps and friable particles, uniformity of grading, loose bulk density, uniformity of loose bulk density, popouts, resistance to freezing and thawing, and drying shrinkage.1.1 This specification covers lightweight aggregates intended for use in concrete masonry units when a prime consideration is to reduce the density of the units.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. Some values have only SI units because the inch-pound equivalents are not used in practice.NOTE 1: Sieve size is identified by its standard designation in Specification E11. The alternative designation given in parentheses is for information only and does not represent a different standard sieve size.1.3 The text of this specification 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 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 lightweight aggregates intended for use in concrete not exposed to the weather, in which the prime consideration is the thermal insulating property of the resulting concrete. Two general types of lightweight aggregate are group I aggregates, which are prepared by expanding products, such as perlite or vermiculite, and group II aggregates which are prepared by expanding, calcining, or sintering products such as blast-furnace slag, clay, diatomite, fly ash, shale, or slate; and aggregates prepared by processing natural materials, such as pumice, scoria, or tuff. The thermal insulating properties of concrete made from the lightweight aggregate under test shall conform to the maximum average thermal conductivity indicated in the specification. To ensure reasonable uniformity in the gradation of successive shipments of lightweight aggregates, fineness modulus determination shall be made periodically. The aggregate shall be composed predominantly of lightweight cellular and granular inorganic material. The test methods for insulating concrete properties include specimen preparation, then concrete density determination, and determinacy of thermal conductivity. When lightweight aggregates covered by this specification are delivered in packages, the name of the manufacturer, type of aggregate, and minimum mass and approximate volume of the contents shall be plainly indicated thereon.1.1 This specification covers lightweight aggregates intended for use in concrete not exposed to the weather, in which the prime consideration is the thermal insulating property of the resulting concrete.1.2 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.1.3 With regard to sieve size and the size of aggregate as determined by the use of testing sieves, the values in inch-pound units are shown for the convenience of the user; however, the standard sieve designation shown in parentheses is the standard value as stated in Specification E11.1.3.1 With regard to other units of measure, 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.1.4 The following precautionary caveat pertains only to the test method portion, Section 7, of the specification: 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： 515元 / 折扣价： 438 元 加购物车