1.1本试验方法提供了确定唯一失效点的程序，用于估算380 mm（14.96 in.）的疲劳寿命长50毫米（1.97英寸）厚度63毫米（2.48英寸）从实验室或现场压实的沥青混凝土上锯下的宽沥青混凝土梁试样，其承受反复弯曲。 1.2正在确定本试验方法的实验室间再现性，并将于2013年6月或之前提供。因此，本试验方法不应用于验收或拒收用于采购目的的材料。 1.3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。 1.4 单位 — 以国际单位制表示的数值应视为标准值。本标准中包含的其他计量单位仅供参考。 1.5 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和健康实践，并确定监管限制的适用性。 ====意义和用途====== 本标准确定的梁试件的实验室疲劳寿命已用于估算重复交通荷载下沥青混凝土路面层的疲劳寿命。尽管沥青混凝土的现场性能受到许多因素（交通变化、速度和漂移；气候变化；荷载之间的休息期；老化等）的影响，但当已知实验室特性以及在路面上行驶的交通轮荷载在层深诱导的应变水平估计时，可以更准确地预测沥青混凝土的现场性能。 笔记 1-本标准产生的结果的质量取决于执行程序的人员的能力以及所用设备的能力、校准和维护。符合规范标准的机构 D3666 通常认为能够胜任和客观的测试/采样/检查等。本标准的用户应注意遵守规范 D3666 单独使用并不能完全保证结果的可靠性。可靠的结果取决于许多因素；遵循规范建议 D3666 或一些类似的可接受指南提供了评估和控制其中一些因素的方法。

1.1 This test method provides procedures for determining a unique failure point for estimating the fatigue life of 380 mm (14.96 in.) long by 50 mm (1.97 in.) thick by 63 mm (2.48 in.) wide asphalt concrete beam specimens sawed from laboratory or field compacted asphalt concrete, which are subjected to repeated flexural bending. 1.2 The between-laboratory reproducibility of this test method is being determined and will be available on or before June 2013. Therefore, this test method should not be used for acceptance or rejection of a material for purchasing purposes. 1.3 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. 1.4 Units — The values stated in SI units are to be regarded as standard. Other units of measurement included in this standard are for information only. 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 and health practices and determine the applicability of regulatory limitations prior to use. ====== Significance And Use ====== The laboratory fatigue life determined by this standard for beam specimens have been used to estimate the fatigue life of asphalt concrete pavement layers under repeated traffic loading. Although the field performance of asphalt concrete is impacted by many factors (traffic variation, speed, and wander; climate variation; rest periods between loads; aging; etc.), it has been more accurately predicted when laboratory properties are known along with an estimate of the strain level induced at the layer depth by the traffic wheel load traveling over the pavement. Note 1—The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Specification D3666 alone does not completely assure reliable results. Reliable results depend on many factors; following the suggestions of Specification D3666 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.