1.1 这些试验方法包括测定细骨料样品的松散、未压实孔隙含量。当在已知级配的任何骨料上测量时，与在相同级配中测试的其他细骨料相比，空隙率提供了该骨料的棱角度、球形度和表面纹理的指示。当在收到的细骨料级配上测量空隙率时，它可以作为细骨料对可使用混合物的可加工性影响的指标。 1.2 空隙率的测量包括三个步骤。两种使用级配细骨料（标准级配或收到的级配），另一种使用几种单独的粒级来测定空隙率: 1.2.1、 标准级配样品（试验方法A）- 该试验方法使用标准细骨料级配，该级配通过将典型细骨料筛分分析中的各个筛级组合而获得。 参见章节 9 用于分级。 1.2.2 单个粒度分数（试验方法B）- 该试验方法使用三种细骨料粒级中的每一种: （a） 2.36毫米（8号）至1.18毫米（16号）； （b） 1.18 mm（编号16）至600μm（编号30）；和 （c） 600微米（编号30）至300微米（编号50）。对于这种测试方法，每个尺寸都要单独测试。 1.2.3 收到的级配（试验方法C）- 本试验方法使用比4.75 mm（4号）筛网更细的细骨料部分。 1.2.4 有关要使用的方法的指导，请参阅“重要性和用途”一节。 1.3 以国际单位制表示的数值应视为标准。 1.4 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.5 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 5.1 试验方法A和B提供了在标准化条件下测定的空隙率，该标准化条件取决于细骨料的颗粒形状和质地。通过这些程序增加的空隙含量表明更大的棱角性、更小的球形度、更粗糙的表面纹理或其组合。空隙率的降低与更圆、球形或表面光滑的细骨料或其组合有关。 5.2 测试方法C测量了负4的未压实空隙含量。 接收材料的75毫米（4号）部分。此空隙率取决于放坡以及粒子形状和纹理。 5.3 在标准级配样品上测定的空隙率（试验方法A）与单独试验的同一样品中三个单独粒级的平均空隙率（测试方法B）不可直接比较。由单一尺寸颗粒组成的样品将具有比分级样品更高的空隙率。因此，使用一种或另一种方法作为形状和纹理的比较测量，并确定使用了哪种测试方法来获得报告的数据。如果样品之间的级配发生变化，试验方法C不会直接提供形状和纹理的指示。 5.3.1 标准级配样品（试验方法A）作为指示级配细骨料颗粒形状特性的快速试验最为有用。 通常，用于构成标准级配样品的材料可以在对细骨料进行单筛分析后从剩余的粒级中获得。 5.3.2 获得和测试单个粒级（测试方法B）比使用分级样品更耗时，并且需要更大的初始样品。然而，测试方法B提供了有关单个尺寸的形状和纹理特征的附加信息。 5.3.3 在收到的分级中测试样品（测试方法C）可能有助于选择各种混合物中使用的组分比例。通常，高空隙率表明可以通过在细骨料中提供额外的细粒来改善材料，或者可能需要更多的胶结材料来填充颗粒之间的空隙。 5.3.4 细骨料的干相对密度（比重）用于计算空隙率。 这些测定空隙率的试验方法的有效性及其与颗粒形状和质地的关系取决于不同粒级的相对密度（比重）是否相等或几乎相等。空隙率实际上是每个粒级体积的函数。如果任何粒级中的岩石或矿物类型或其孔隙率变化显著，则可能有必要确定试验中使用的粒级的比重。 5.4 试验方法A、B或C中的空隙率信息将用作性能指标，例如:水硬性水泥混凝土的搅拌用水需求；配制灌浆或砂浆时的流动性、泵送性或可加工性因素；或者，在沥青混凝土中，细骨料对矿物骨料稳定性和空隙的影响； 或基层集料的细集料部分的稳定性。

1.1 These test methods cover the determination of the loose, uncompacted void content of a sample of fine aggregate. When measured on any aggregate of a known grading, void content provides an indication of that aggregate's angularity, sphericity, and surface texture compared with other fine aggregates tested in the same grading. When void content is measured on an as-received fine-aggregate grading, it can be an indicator of the effect of the fine aggregate on the workability of a mixture in which it may be used. 1.2 Three procedures are included for the measurement of void content. Two use graded fine aggregate (standard grading or as-received grading), and the other uses several individual size fractions for void content determinations: 1.2.1 Standard Graded Sample (Test Method A)— This test method uses a standard fine aggregate grading that is obtained by combining individual sieve fractions from a typical fine aggregate sieve analysis. See the Section 9 for the grading. 1.2.2 Individual Size Fractions (Test Method B)— This test method uses each of three fine aggregate size fractions: (a) 2.36 mm (No. 8) to 1.18 mm (No. 16); (b) 1.18 mm (No. 16) to 600 μm (No. 30); and (c) 600 μm (No. 30) to 300 μm (No. 50). For this test method, each size is tested separately. 1.2.3 As-Received Grading (Test Method C)— This test method uses that portion of the fine aggregate finer than a 4.75 mm (No. 4) sieve. 1.2.4 See the section on Significance and Use for guidance on the method to be used. 1.3 The values stated in SI units shall be regarded as 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. ====== Significance And Use ====== 5.1 Test Methods A and B provide percent void content determined under standardized conditions which depend on the particle shape and texture of a fine aggregate. An increase in void content by these procedures indicates greater angularity, less sphericity, rougher surface texture, or combinations thereof. A decrease in void content results is associated with more rounded, spherical, or smooth-surfaced fine aggregate, or a combination thereof. 5.2 Test Method C measures the uncompacted void content of the minus 4.75 mm (No. 4) portion of the as-received material. This void content depends on grading as well as particle shape and texture. 5.3 The void content determined on the standard graded sample (Test Method A) is not directly comparable with the average void content of the three individual size fractions from the same sample tested separately (Test Method B). A sample consisting of single-size particles will have a higher void content than a graded sample. Therefore, use either one method or the other as a comparative measure of shape and texture, and identify which test method has been used to obtain the reported data. Test Method C does not provide an indication of shape and texture directly if the grading from sample to sample changes. 5.3.1 The standard graded sample (Test Method A) is most useful as a quick test which indicates the particle shape properties of a graded fine aggregate. Typically, the material used to make up the standard graded sample can be obtained from the remaining size fractions after performing a single sieve analysis of the fine aggregate. 5.3.2 Obtaining and testing individual size fractions (Test Method B) are more time consuming and require a larger initial sample than using the graded sample. However, Test Method B provides additional information concerning the shape and texture characteristics of individual sizes. 5.3.3 Testing samples in the as-received grading (Test Method C) may be useful in selecting proportions of components used in a variety of mixtures. In general, high void content suggests that the material could be improved by providing additional fines in the fine aggregate or more cementitious material may be needed to fill voids between particles. 5.3.4 The dry relative denstiy (specific gravity) of the fine aggregate is used in calculating the void content. The effectiveness of these test methods of determining void content and its relationship to particle shape and texture depends on the relative density (specific gravity) of the various size fractions being equal, or nearly so. The void content is actually a function of the volume of each size fraction. If the type of rock or minerals, or its porosity, in any of the size fractions varies markedly it may be necessary to determine the specific gravity of the size fractions used in the test. 5.4 Void content information from Test Methods A, B, or C will be useful as an indicator of properties such as: the mixing water demand of hydraulic cement concrete; flowability, pumpability, or workability factors when formulating grouts or mortars; or, in bituminous concrete, the effect of the fine aggregate on stability and voids in the mineral aggregate; or the stability of the fine-aggregate portion of a base course aggregate.