1.1 本标准中所述的试验方法测量单个垂直或倾斜深基础构件或一组构件在静态轴向张力下加载时的轴向挠度。这些方法适用于所有类型的深基础或深基础系统，因为它们易于测试。其单个部件在本文中称为元件，其功能类似于或类似于钻孔轴；灌注桩（螺旋钻孔灌注桩、桩夹和泥浆墙）；打入桩，如预制混凝土桩、木桩或型钢（钢管或宽翼缘梁）； 或任何数量的其他元件类型，无论其安装方法如何。尽管测试方法可用于测试单个元件或元件组，但测试结果可能无法代表整个深基础系统的长期性能。第4节概述了试验方法。 1.2 本标准规定了在静态轴向拉伸载荷下测试深基础元件的最低要求。项目计划、规范、规定或其任何组合可提供满足特定测试计划目标所需的额外要求和程序。 负责基础设计的工程师（此处称为基础工程师）应批准对本标准要求的任何偏差、删除或添加。（例外情况:适用于试验装置的试验负载不得超过设计试验装置的工程师确定的额定容量。） 1.3 此处指定为“可选”的仪器和程序可能会产生不同的测试结果，并且只有在获得基础工程师批准后才能使用。“应”一词表示强制性规定，“应”一词表示建议或咨询性规定。 祈使句表示强制性规定。 1.4 基础工程师应解释从本标准程序中获得的测试结果，以预测建造基础中使用的构件的实际性能和充分性。 1.5 有资格执行此类工作的工程师应设计并批准所有加载装置、加载构件和支撑架。基础工程师应设计或规定测试程序。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。 本标准还包括仅供解释或咨询使用的插图和附录。 1.6 单位- 以国际单位制或英寸-磅单位表示的数值应单独视为标准值。每个系统中规定的值可能不是精确的等效值；因此，每个系统应相互独立使用。将两个系统的值合并可能会导致不符合标准。 1.7 在处理英寸磅单位时，使用英寸磅单位的重力系统。在这个系统中，磅[lbf]表示力[重量]的单位，而质量的单位是段塞。 除非涉及动态[F=ma]计算，否则未给出合理化的段塞单元。 1.8 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 . 本标准中用于规定如何收集、记录和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。考虑工程数据分析方法中使用的有效数字超出了本标准的范围。 1.9 本标准中用于指定数据收集、计算或记录方式的方法与数据在设计或其他用途中或两者中的应用精度没有直接关系。如何应用使用本标准获得的结果超出了其范围。 1.10 本标准提供了有组织的信息收集或一系列选项，并不推荐具体的行动方案。 本文件不能取代教育或经验，应与专业判断一起使用。并非本标准的所有方面都适用于所有情况。本ASTM标准不代表或取代必须根据其判断给定专业服务的充分性的谨慎标准，也不应在不考虑项目的许多独特方面的情况下应用本文件。本文件标题中的“标准”一词仅表示该文件已通过ASTM共识程序获得批准。 1.11 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。 1.12 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 现场试验提供了施加在深基础上的轴向载荷与由此产生的轴向运动之间最可靠的关系。试验结果还可以提供用于评估沿构件的侧剪切阻力分布和长期荷载-挠度行为的信息。基础工程师可评估测试结果，以确定在应用适当的安全系数后，构件或构件组是否具有静态承载力、荷载响应和工作荷载下的挠度，以满足支撑基础的要求。 当作为多元件测试计划的一部分执行时，基础工程师还可以使用结果来评估不同尺寸和类型的基础元件的可行性以及测试场地的可变性。 5.2 如果可行且不超过元件或元件帽上的安全结构载荷（以下除非另有说明，“元件”和“元件组”可酌情互换），施加的最大载荷应达到破坏载荷，基础工程师可根据该载荷确定元件的轴向静态拉伸载荷能力。 通过减少基础构件的长度、数量和/或尺寸，达到破坏荷载的测试可以帮助基础工程师提高基础设计的效率。 5.3 如果认为向倾斜构件施加轴向试验荷载不切实际，基础工程师可以选择使用附近垂直构件的轴向试验结果来评估倾斜构件的轴向承载力。基础工程师也可以选择对倾斜构件进行双向轴向试验( D8169/D8169M ). 5.4 不同的负载测试程序可能导致不同的负载- 位移曲线。快速测试( 10.1.2 )和恒速率抗拔试验( 10.1.4 )通常可以在几个小时内完成。两者在概念上都很简单，随着载荷的增加，加载元件的速度相对较快。维护测试( 10.1.3 )以更大的增量和更长的间隔加载元件，这可能会导致测试持续时间显著更长。由于荷载增量较大，破坏荷载的确定可能不太精确，但维持试验被认为可以提供更多关于蠕变位移的信息。 尽管恒速率抗拔试验的控制较为复杂（对于大直径或承载力元件来说并不常见），但该试验可能会产生承载力的最佳定义。基础工程师必须权衡程序的复杂性和其他限制与任何感知的好处。 5.5 本标准的范围不包括对受拉地基承载力的分析，但为了适当分析试验数据，重要的是适当记录有关影响导出的静态轴向拉伸承载力的因素的信息。 这些因素可能包括但不限于以下方面: 5.5.1 元件中的潜在残余载荷可能会影响沿元件轴的载荷分布。 5.5.2 来自测试元件的摩擦载荷与从反应元件转移到土壤的向下摩擦的可能相互作用，反应元件在测试元件尖端水平以上的土壤中获得部分或全部支撑。 5.5.3 由元件驱动、施工填充和其他施工操作引起的土壤孔隙水压力变化，可能会影响相对不透水土壤（如粘土和粉土）中摩擦支撑的测试结果。 5.5.4 测试时和最终施工后条件之间的差异，例如坡度或地下水位的变化。 5.5.5 开挖和冲刷等活动可能导致支撑测试元件的土壤损失。 5.5.6 一个组或一个元素组中的元素的性能与单个孤立元素的性能可能存在差异。 5.5.7 蠕变、环境对元件材料的影响、之前未考虑的负摩擦载荷和强度损失等因素对元件长期性能的影响。 5.5.8 待支撑结构的类型，包括结构对沉降的敏感性以及活荷载和恒荷载之间的关系。 5.5.9 应用某些验收标准或解释方法可能需要的特殊测试程序。 5.5.10 要求未测试元件具有与测试元件基本相同的条件，包括但不限于地下条件、元件类型、长度、尺寸和刚度，以及元件安装方法和设备，以便将测试结果应用或外推到此类其他元件是有效的。 对于混凝土构件，有时需要在试验构件中使用更多的钢筋，以便安全地进行试验，达到预定的要求试验荷载。在这种情况下，基础工程师应考虑测试元件和未测试元件之间的刚度差异。 5.5.11 拉伸试验有时用于验证构件的压缩能力和拉伸能力。当承受拉伸载荷时，与承受压缩载荷的构件相比，构件可能具有不同的刚度和结构承载力。 注1: 这些测试方法产生的结果的质量取决于执行测试的人员的能力，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。这些测试方法的用户应注意遵守实践 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 The test methods described in this standard measure the axial deflection of an individual vertical or inclined deep foundation element or group of elements when loaded in static axial tension. These methods apply to all types of deep foundations, or deep foundation systems, as they are practical to test. The individual components of which are referred to herein as elements that function as, or in a manner similar to, drilled shafts; cast-in-place piles (augered cast-in-place piles, barrettes, and slurry walls); driven piles, such as pre-cast concrete piles, timber piles or steel sections (steel pipes or wide flange beams); or any number of other element types, regardless of their method of installation. Although the test methods may be used for testing single elements or element groups, the test results may not represent the long-term performance of the entire deep foundation system. A summary of the test methods is contained in Section 4. 1.2 This standard provides minimum requirements for testing deep foundation elements under static axial tensile load. Project plans, specifications, provisions, or any combination thereof may provide additional requirements and procedures as needed to satisfy the objectives of a particular test program. The engineer in charge of the foundation design, referred to herein as the foundation engineer, shall approve any deviations, deletions, or additions to the requirements of this standard. (Exception: the test load applies to the testing apparatus shall not exceed the rated capacity established by the engineer who designed the testing apparatus.) 1.3 Apparatus and procedures herein designated “optional” may produce different test results and may be used only when approved by the foundation engineer. The word “shall” indicates a mandatory provision, and the word “should” indicates a recommended or advisory provision. Imperative sentences indicate mandatory provisions. 1.4 The foundation engineer should interpret the test results obtained from the procedures of this standard to predict the actual performance and adequacy of elements used in the constructed foundation. 1.5 An engineer qualified to perform such work shall design and approve all loading apparatus, loaded members, and support frames. The foundation engineer shall design or specify the test procedures. 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 requirements of the standard. This standard also includes illustrations and appendices intended only for explanatory or advisory use. 1.6 Units— The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. 1.7 The gravitational system of inch-pound units is used when dealing with inch-pound units. In this system, the pound [lbf] represents a unit of force [weight], while the unit for mass is slug. The rationalized slug unit is not given, unless dynamic [F=ma] calculations are involved. 1.8 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026 . The procedure used to specify how data are collected, recorded and calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that should generally 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 data. 1.9 The method used to specify how data are collected, calculated, or recorded in this standard is not directly related to the accuracy to which the data can be applied in design or other uses, or both. How one applies the results obtained using this standard is beyond its scope. 1.10 This standard offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this standard may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process. 1.11 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. 1.12 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 Field tests provide the most reliable relationship between the axial load applied to a deep foundation and the resulting axial movement. Test results may also provide information used to assess the distribution of side shear resistance along the element and the long-term load-deflection behavior. The foundation engineer may evaluate the test results to determine if, after applying appropriate factors of safety, the element or group of elements has a static capacity, load response and deflection at service load satisfactory to support the foundation. When performed as part of a multiple-element test program, the foundation engineer may also use the results to assess the viability of different sizes and types of foundation elements and the variability of the test site. 5.2 If feasible and without exceeding the safe structural load on the element or element cap (hereinafter unless otherwise indicated, “element” and “element group” are interchangeable as appropriate), the maximum load applied should reach a failure load from which the foundation engineer may determine the axial static tensile load capacity of the element. Tests that achieve a failure load may help the foundation engineer improve the efficiency of the foundation design by reducing the foundation element length, quantity, and/or size. 5.3 If deemed impractical to apply axial test loads to an inclined element, the foundation engineer may elect to use axial test results from a nearby vertical element to evaluate the axial capacity of the inclined element. The foundation engineer may also elect to use a bi-directional axial test on an inclined element ( D8169/D8169M ). 5.4 Different loading test procedures may result in different load-displacement curves. The Quick Test ( 10.1.2 ) and Constant Rate of Uplift Test ( 10.1.4 ) typically can be completed in a few hours. Both are simple in concept, loading the element relatively quickly as load is increased. The Maintained Test ( 10.1.3 ) loads the element in larger increments and for longer intervals, which could cause the test duration to be significantly longer. Because of the larger load increments the determination of the failure load can be less precise, but the Maintained Test is thought to give more information on creep displacement. Although control of the Constant Rate of Uplift Test is somewhat more complicated (and uncommon for large diameter or capacity elements), the test may produce the best possible definition of capacity. The foundation engineer must weigh the complexity of the procedure and other limitations against any perceived benefit. 5.5 The scope of this standard does not include analysis for foundation capacity in tension, but in order to analyze the test data appropriately it is important that information on factors that affect the derived mobilized static axial tensile capacity are properly documented. These factors may include, but are not limited to, the following: 5.5.1 Potential residual loads in the element which could influence the interpreted distribution of load along the element shaft. 5.5.2 Possible interaction of friction loads from test element with downward friction transferred to the soil from reaction elements obtaining part or all of their support in soil at levels above the tip level of the test element. 5.5.3 Changes in pore water pressure in the soil caused by element driving, construction fill, and other construction operations which may influence the test results for frictional support in relatively impervious soils such as clay and silt. 5.5.4 Differences between conditions at time of testing and after final construction such as changes in grade or groundwater level. 5.5.5 Potential loss of soil supporting the test element from such activities as excavation and scour. 5.5.6 Possible differences in the performance of an element in a group or of an element group from that of a single isolated element. 5.5.7 Effect on long-term element performance of factors such as creep, environmental effects on element material, negative friction loads not previously accounted for, and strength losses. 5.5.8 Type of structure to be supported, including sensitivity of structure to settlements and relation between live and dead loads. 5.5.9 Special testing procedures which may be required for the application of certain acceptance criteria or methods of interpretation. 5.5.10 Requirement that non-tested element(s) have essentially identical conditions to those for tested element(s) including, but not limited to, subsurface conditions, element type, length, size and stiffness, and element installation methods and equipment, so that application or extrapolation of the test results to such other elements is valid. For concrete elements, it is sometimes necessary to use higher amounts of reinforcement in the test elements in order to safely conduct the test to the predetermined required test load. In such cases, the foundation engineer shall account for the difference in stiffness between the test elements and non-tested elements. 5.5.11 Tension tests are sometimes used to validate element compression capacity in addition to tension capacity. When subjected to tension loads, elements may have different stiffness and structural capacity compared to elements subjected to compression loads. Note 1: The quality of the result produced by these test methods 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 these test methods 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.