1.1本试验方法包括在饱和粘土和粉土中进行现场十字板试验，以测定不排水抗剪强度。要评估试验的适用性和解释，需要了解进行每个十字板试验的土壤性质。本试验不适用于试验期间可能允许排水的砂土。 1.2本试验方法涉及陆上试验和钻孔试验，或通过自钻或连续推土方法从地面进行试验。 该方法不专门针对可能需要特殊测试要求或设备变化的海洋测试。用户可参考ASTM STP 1014，了解有关现场叶片剪切试验的更多信息。 1.3该方法通常与流体旋转钻井（D 5783）结合使用 )或空心杆螺旋钻（D 6151 ). 一些设备将叶片缩回防护靴中，用于推进和增量测试。取样，例如使用薄壁管（D 1587 )通常与叶片测试相结合。 根据实践（D 5434）报告地下岩土勘探 ). 1.4粘性土的不排水抗剪强度和敏感性也可以在无侧限压缩D 2166中测量 和实验室叶片试验（D 4648 ). 1.5以国际单位制表示的数值应视为标准。括号中给出了英制单位。 1.6 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====== 本试验方法提供了细粒粘土和粉土或其他细粒岩土材料（如尾矿、有机淤泥和需要测定不排水强度的物质）的现场不排水剪切强度的指示。本试验适用于不排水强度小于200 kPa（2 tsf）的土壤。非常敏感的土壤可以在插入叶片期间重塑。 该试验方法广泛用于各种岩土工程勘察，以评估饱和细粒土总应力分析的快速加载强度- 颗粒粘土和粉土。该测试通常与其他现场和实验室测试一起进行。 通常对十字板试验的峰值不排水剪切阻力进行校正，以确定岩土分析的不排水剪切强度。要求测试的机构必须解释这些数据，以确定强度分析的适用性。为岩土分析推荐十字板试验的适用性超出了本标准的范围。有关这些修正系数的一般使用信息，请参阅附录X1。 该方法不适用于砂、砾石或其他高渗透性土壤。根据本标准中所述的剪切速率，砂透镜体（如果存在）将允许全部或部分排水。渗透性较高的土壤在快速剪切时会膨胀或坍塌，并产生负孔隙压力或正孔隙压力，这些压力可能在剪切过程中消散，也可能不会消散。检查正在测试的土壤类型很重要。在测试之前或之后对土壤进行采样，以了解测试土壤的排水条件（渗透性），这是非常有益的。 该测试通常在钻孔中进行，或采用自推或自钻或推（导叶）方法。该方法也适用于在较浅深度进行的手持式叶片剪切试验，然而，手持式设备可能不太准确，因为它可能更难保持叶片/杆的稳定性和垂直度。 笔记 2-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D 3740标准的机构 通常认为能够胜任和客观测试。本标准的用户应注意遵守实施规程D 3740 本身并不能保证可靠的结果。可靠的结果取决于许多因素；标准实施规程D 3740 提供了一种评估其中一些因素的方法。

1.1 This test method covers the field vane test in saturated clay and silt soils for determination of undrained shear strength. Knowledge of the nature of the soil in which each vane test is to be made is necessary for assessment of the applicability and interpretation of the test. The test is not applicable for sandy soils which may allow drainage during the test. 1.2 This test method addresses testing on land and for testing in drill holes or by self drilling or continuous push methods from the ground surface. This method does not address specifically marine testing where special test requirements or variations in equipment may be required. The user is referred to ASTM STP 1014 for additional information on in-place vane shear testing. 1.3 This method is often used in conjunction with fluid rotary drilling (D 5783 ) or hollow-stem augers (D 6151 ). Some apparatuses have the vane retracted in protective shoe for advancement and incremental testing. Sampling, such as with thin wall tubes (D 1587 ) is often combined with vane testing. Subsurface geotechnical explorations are reported in accordance with practice (D 5434 ). 1.4 Undrained shear strength and sensitivity of cohesive soils can also be measured in Unconfined Compression D 2166 and Laboratory Vane Test (D 4648 ). 1.5 The values stated in SI units are to be regarded as the standard. English (Imperial) units are given in parentheses. 1.6 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 ====== This test method provides an indication of in-situ undrained shear strength of fine- grained clays and silts or other fine geomaterials such as mine tailings, organic muck, and substances where undrained strength determination is required. The test is applicable to soils with undrained strengths of less than 200 kPa (2 tsf). Very sensitive soils can be remolded during vane insertion. This test method is used extensively in a variety of geotechnical explorations to evaluate rapid loading strength for total stress analysis of saturated fine-grained clays and silts. The test is routinely performed in conjunction with other field and laboratory tests. The peak undrained shear resistance of the vane test is commonly corrected to determine the undrained shear strength for geotechnical analysis. The agency requesting the testing must interpret these data to determine applicability for strength analysis. It is beyond the scope of this standard to recommend applicability of vane testing for geotechnical analysis. For information on the general use of these correction factors, consult Appendix X1. This method is not applicable in sands, gravels, or other high permeability soils. With the shearing rates described in this standard, sand lenses, if present, will allow total or partial drainage. Soils with higher permeability, in rapid shear, can dilate or collapse and generate negative or positive pore pressures which may, or may not, dissipate in the shearing process. It is important to check the soil type being tested. It is very beneficial to sample the soil either before or after testing, to understand the drainage conditions (permeability) of the soil tested. This test is often performed in drilled boreholes or with self-push or self-drilling or pushed (vane shoe) methods. This method also applies to hand held vane shear tests performed at shallow depths, however, hand held equipment may be less accurate, because it may be more difficult to maintain vane/rod stability and verticality. Note 2—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 D 3740 are generally considered capable of competent and objective testing. Users of this standard are cautioned that compliance with Practice D 3740 does not in itself assure reliable results. Reliable results depend on many factors; Standard Practice D 3740 provides a means of evaluating some of those factors.