1.1 本试验方法包括测定承受单轴压缩的冻土圆柱试样的蠕变行为。它规定了用于确定偏差蠕变条件下冻土的应力-应变时间或强度与应变率关系的仪器、仪表和程序。 1.2 虽然该试验方法是最常用的方法之一，但人们认识到，与某些特定应用相关的冻土蠕变特性也可以通过一些替代程序获得，例如应力松弛试验、简单剪切试验和梁弯曲试验。三轴试验条件下的蠕变试验将包含在另一个标准中。 1.3 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。 1.4 所有观察值和计算值应符合实践中确定的有效数字和舍入准则 D6026 . 1.4.1 为了将测量值或计算值与规定限值进行比较，测量值或计算值应四舍五入至规定限值中最接近的小数或有效数字。 1.4.2 本标准中用于规定如何收集/记录或计算数据的程序被视为行业标准。此外，它们代表了通常应保留的有效数字。使用的程序不考虑材料变化、获取数据的目的、特殊目的研究或用户目标的任何考虑因素；通常的做法是增加或减少报告数据的有效位数，以与这些考虑因素相称。 考虑工程设计分析方法中使用的有效数字超出了本标准的范围。 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、健康和环境实践，并确定监管限制的适用性。 1.6 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. 了解冻土的力学性质对多年冻土工程至关重要。蠕变试验数据对于埋置在冻土中或冻土上的大多数基础元件的设计是必要的。它们可以预测桩和浅基础在工作荷载下随时间变化的沉降，并估计其短期和长期承载力。蠕变试验还为永久使用的地下结构的稳定性分析提供了定量参数。 5.2 必须认识到，现场冻土的结构及其在荷载下的行为可能与实验室中人工制备的试样有很大不同。这主要是因为，除了小型实验室样本中包含的孔隙冰外，天然永久冻土地面可能包含许多不同形式和尺寸的冰。 这些大型地面冰包体（如冰透镜体，任何尺寸的主要水平透镜状冰体）将极大地影响全尺寸工程结构的时间相关行为。 5.3 为了获得可靠的结果，需要高质量的完整代表性多年冻土样本进行蠕变试验。样品质量取决于取样的冻土类型、取样时的现场热条件、取样方法以及试验前的运输和储存程序。最好的测试程序可能会被质量差的样品毁掉。此外，必须始终记住，将实验室结果应用于实际问题需要非常谨慎和工程判断。 注1: 本标准产生的结果的质量取决于执行该标准的人员的能力，以及所用设备和设施的适用性。 符合实践标准的机构 D3740 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惯例 D3740 本身并不能保证可靠的结果。可靠的结果取决于许多因素；实践 D3740 提供了一种评估其中一些因素的方法。

1.1 This test method covers the determination of the creep behavior of cylindrical specimens of frozen soil, subjected to uniaxial compression. It specifies the apparatus, instrumentation, and procedures for determining the stress-strain-time, or strength versus strain rate relationships for frozen soils under deviatoric creep conditions. 1.2 Although this test method is one that is most commonly used, it is recognized that creep properties of frozen soil related to certain specific applications, can also be obtained by some alternative procedures, such as stress-relaxation tests, simple shear tests, and beam flexure tests. Creep testing under triaxial test conditions will be covered in another standard. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026 . 1.4.1 For the purposes of comparing, a measured or calculated value(s) with specified limits, the measured or calculated value(s) shall be rounded to the nearest decimal or significant digits in the specified limits. 1.4.2 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design. 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6 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 Understanding the mechanical properties of frozen soils is of primary importance to permafrost engineering. Data from creep tests are necessary for the design of most foundation elements embedded in, or bearing on frozen ground. They make it possible to predict the time-dependent settlements of piles and shallow foundations under service loads, and to estimate their short- and long-term bearing capacity. Creep tests also provide quantitative parameters for the stability analysis of underground structures that are created for permanent use. 5.2 It must be recognized that the structure of frozen soil in situ and its behavior under load may differ significantly from that of an artificially prepared specimen in the laboratory. This is mainly due to the fact that natural permafrost ground may contain ice in many different forms and sizes, in addition to the pore ice contained in a small laboratory specimen. These large ground-ice inclusions (such as ice lenses, a dominant horizontal, lens-shaped body of ice of any dimension) will considerably affect the time-dependent behavior of full-scale engineering structures. 5.3 In order to obtain reliable results, high-quality intact representative permafrost samples are required for creep tests. The quality of the sample depends on the type of frozen soil sampled, the in situ thermal condition at the time of sampling, the sampling method, and the transportation and storage procedures prior to testing. The best testing program can be ruined by poor-quality samples. In addition, one must always keep in mind that the application of laboratory results to practical problems requires much caution and engineering judgment. Note 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.