1.1 本试验方法包括测定水硬性水泥浆中的早期硬化。 1.2 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.3 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户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。( 警告- 新鲜的水硬性胶结混合物具有腐蚀性，长时间接触可能会导致皮肤和组织化学烧伤。） 2. 1.4 本标准的文本引用了提供解释材料的注释和脚注。这些注释和脚注（不包括表和图中的注释和脚注）不应视为本标准的要求。 1.5 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）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》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 本试验方法的目的是确定水泥浆早期硬化的程度，或确定水泥是否符合早期硬化的规范限制。 5.2 当用于确定符合规范极限时，规范要求通常以最小允许最终贯入度表示，以百分比表示，根据计算部分计算。 当用于估计水泥表现出早期硬化的相对趋势时，如果采用程序部分中描述的重新混合程序，则可以获得额外的有价值的信息。在某些情况下，可以通过比较初始测试和混合过程中的行为来进行判断，以区分相对较不严重和较不持久的早期硬化倾向（假集）和更持久的倾向，从而更严重（闪光集）。 5.3 从浇筑和搬运的角度来看，水泥中的严重假凝可能会造成困难，但当混凝土搅拌时间比通常情况下长时（通常发生在运输过程中），或在浇筑或运输之前重新搅拌时（如混凝土泵送操作中），则不太可能造成困难。 当混凝土在固定式搅拌机中短时间搅拌，并在非搅拌设备中运输至模板时（例如在某些铺路作业中），以及在现场搅拌站中制备混凝土时，这一点最为明显。 5.4 假凝严重的水泥通常需要稍多的水才能产生相同的稠度，这可能会导致强度稍低和干燥收缩增加。 5.5 由于假凝结而导致的早期硬化不太可能导致水泥未达到适用的凝结时间要求。 5.6 由闪凝引起的早期硬化（取决于严重程度）可能导致水泥未达到适用的凝结时间要求。

1.1 This test method covers the determination of early stiffening in hydraulic-cement paste. 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 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. ( Warning— Fresh hydraulic-cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.) 2 1.4 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. 1.5 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 The purpose of this test method is to determine the degree to which a cement paste develops early stiffening or to establish whether or not a cement complies with a specification limit on early stiffening. 5.2 When used for establishing compliance with a specification limit, the specification requirement is customarily stated in terms of the minimum allowable final penetration, in percent, calculated in accordance with the Calculation Section. When used for estimating the relative tendency of a cement to manifest early stiffening, additional information of value may be obtained if the remix procedure described in the Procedure Section is employed. Under some conditions, a judgment may be made by comparing the behavior in the initial test and in the remix procedure to differentiate a relatively less serious and less persistent tendency to early stiffening (false set) from one that is more persistent and, consequently, more serious (flash set). 5.3 Severe false setting in a cement may cause difficulty from a placing and handling standpoint, but it is not likely to cause difficulties where concrete is mixed for a longer time than usual, as usually occurs in transit mixing, or where it is remixed prior to placing or transporting, as occurs in concrete pumping operations. It is most likely to be noticeable where concrete is mixed for a short period of time in stationary mixers and transported to the forms in non-agitating equipment, such as on some paving jobs, and when concrete is made in an on-site batch plant. 5.4 Cements with severe false setting usually require slightly more water to produce the same consistency, which may be expected to result in slightly lower strengths and increased drying shrinkage. 5.5 Early stiffening resulting from false set is not likely to cause a cement to fail the applicable time of setting requirement. 5.6 Early stiffening resulting from flash set, depending on severity, can cause a cement to fail the applicable time of setting requirement.