1.1 该试验方法包括使用阶梯等温法（SIM）进行拉伸蠕变和拉伸蠕变断裂性能的加速试验。 1.2 试验方法主要针对土工合成材料加固材料，如纱线、土工格栅肋条或窄土工织物试样。 1.3 SIM试验是基于时间-温度叠加程序的横向无侧限试验。 1.4 拉伸试验应在SIM试验之前完成，其结果用于确定后续SIM试验的应力水平，该应力水平根据极限拉伸强度（T ULT )。此外，拉伸测试可以被设计为提供适合SIM结果的初始弹性应变分布的估计。 1.5 斜坡和保持（R+H）测试可以与SIM测试一起完成。它们被设计为提供适用于SIM结果的初始弹性和初始快速蠕变应变水平的额外估计。 1.6 该方法可用于建立土工合成材料的持续荷载蠕变和蠕变断裂特性。该方法的结果将用于增加试验方法的结果 D5262 并且不能用作确定土工合成材料的长期蠕变和蠕变断裂行为的唯一依据。 1.7 以国际单位制表示的数值应视为标准。本标准中不包括其他计量单位。 1.8 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。 1.9 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 阶跃等温方法的使用减少了蠕变发生和相关数据获取所需的时间。 5.2 声明载于 1.6 在意义和用途以及标准范围方面都非常重要。 5.3 蠕变试验数据用于计算材料的蠕变模量作为时间的函数。然后，这些数据用于预测用于加固应用的土工合成材料的长期蠕变变形。 注1: 目前，SIM测试主要集中在由聚酯、芳纶、聚酰胺、聚乙烯醇（PVA）、聚丙烯纱线和窄条制成的编织和针织土工格栅以及编织土工布上。还需要对其他材料进行更多的相关性研究。 5.4 蠕变断裂试验数据用于开发蠕变应力与断裂时间相关的回归线。 这些结果预测了土工合成材料在加固应用中的长期断裂强度。 5.5 拉伸试验用于确定极限拉伸强度（T ULT )并确定SIM测试的弹性应力、应变及其变化。 5.6 斜坡和保持（R+H）测试是为了确定在负载斜坡峰值之后的快速响应的短时间内所经历的蠕变应变的范围。

1.1 This test method covers accelerated testing for tensile creep, and tensile creep-rupture properties using the Stepped Isothermal Method (SIM). 1.2 The test method is focused on geosynthetic reinforcement materials such as yarns, ribs of geogrids, or narrow geotextile specimens. 1.3 The SIM tests are laterally unconfined tests based on time-temperature superposition procedures. 1.4 Tensile tests are to be completed before SIM tests and the results are used to determine the stress levels for subsequent SIM tests defined in terms of the percentage of Ultimate Tensile Strength (T ULT ). Additionally, the tensile test can be designed to provide estimates of the initial elastic strain distributions appropriate for the SIM results. 1.5 Ramp and Hold (R+H) tests may be completed in conjunction with SIM tests. They are designed to provide additional estimates of the initial elastic and initial rapid creep strain levels appropriate for the SIM results. 1.6 This method can be used to establish the sustained load creep and creep-rupture characteristics of a geosynthetic. Results of this method are to be used to augment results of Test Method D5262 and may not be used as the sole basis for determination of long-term creep and creep-rupture behavior of geosynthetic material. 1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 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. ====== Significance And Use ====== 5.1 Use of the Stepped Isothermal Method decreases the time required for creep to occur and the obtaining of the associated data. 5.2 The statements set forth in 1.6 are very important in the context of significance and use, as well as scope of the standard. 5.3 Creep test data are used to calculate the creep modulus of materials as a function of time. These data are then used to predict the long-term creep deformation expected of geosynthetics used in reinforcement applications. Note 1: Currently, SIM testing has focused mainly on woven and knitted geogrids and woven geotextiles made from polyester, aramid, polyaramid, poly-vinyl alcohol (PVA), and polypropylene yarns and narrow strips. Additional correlation studies on other materials are needed. 5.4 Creep-rupture test data are used to develop a regression line relating creep stress to rupture time. These results predict the long-term rupture strength expected for geosynthetics in reinforcement applications. 5.5 Tensile testing is used to establish the ultimate tensile strength (T ULT ) of a material and to determine elastic stress, strain, and variations thereof for SIM tests. 5.6 Ramp and Hold (R+H) testing is done to establish the range of creep strains experienced in the brief period of very rapid response following the peak of the load ramp.