1.1这些试验方法仅限于测定土壤材料中两种水平行波的速度；一次压缩( P波 )和二次剪切( 横波 )波浪。该标准假设用于分析获得的数据的方法基于测量距离上的首次到达时间或间隔到达时间。 1.2讨论了可接受的解释程序和设备，如震源、接收器和记录系统。其他项目包括钻孔间距、钻孔、套管、灌浆、偏差测量和实际测试程序。 1.3这些测试方法主要涉及实际测试程序、数据解释和设备规范，这些设备将产生统一的测试结果。 1.4所有记录和计算值应符合实施规程D6026中制定的有效数字和舍入指南。 1.4.1用于规定如何在这些试验方法中收集/记录和计算数据的程序被视为行业标准。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。比这些试验方法中规定的更有效数字或更高灵敏度的测量不应视为不符合本标准。 1.5 单位- 以国际单位制或英寸-磅单位表示的数值[括号内]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。以国际单位制以外的单位报告试验结果不应视为不符合本试验方法。 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====== 5.1地震跨孔法为设计师提供了与所述材料的地震波速相关的信息 (1) . 2. 该数据可按如下方式使用: 5.1.1静态/动态分析输入； 5.1.2用于计算剪切模量、杨氏模量和泊松比（假设密度已知或假设）； 5.1.3使用适当的建筑规范确定地震场地类别；和 5.1.4用于评估液化潜力。 5.2试验方法固有的基本假设如下: 5.2.1假设水平分层。 5.2.2斯奈尔折射定律适用于纵波和横波以及由井间测试得出的速度。如果在分析井间地震测试数据时未考虑斯奈尔折射定律，则报告应如此说明，并且在地层变化附近的某些深度段内，获得的纵波和横波速度可能不可靠 (2) . 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设备和设施的适用性。符合实施规程D3740标准的机构通常被认为能够胜任和客观的测试/采样/检查等。这些试验方法的使用者应注意，遵守实施规程D3740本身并不能确保可靠的结果。可靠的结果取决于许多因素；实践D3740提供了评估其中一些因素的方法。

1.1 These test methods are limited to the determination of the velocity of two types of horizontally travelling seismic waves in soil materials; primary compression ( P-wave ) and secondary shear ( S-wave ) waves. The standard assumes that the method used to analyze the data obtained is based on first arrival times or interval arrival times over a measured distance. 1.2 Acceptable interpretation procedures and equipment, such as seismic sources, receivers, and recording systems are discussed. Other items addressed include borehole spacing, drilling, casing, grouting, deviation surveys, and actual test procedures. 1.3 These test methods are primarily concerned with the actual test procedure, data interpretation, and specifications for equipment which will yield uniform test results. 1.4 All recorded and calculated values shall conform to the guide for significant digits and rounding established in Practice D6026. 1.4.1 The procedures used to specify how data are collected/recorded and calculated in these test methods are regarded as the industry standard. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives. Measurements made to more significant digits or better sensitivity than specified in these test methods shall not be regarded a nonconformance with this standard. 1.5 Units— The values stated in either SI units or inch-pound units [presented in brackets] 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. Reporting of test results in units other than SI shall not be regarded as nonconformance with this test method. 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 ====== 5.1 The seismic crosshole method provides a designer with information pertinent to the seismic wave velocities of the materials in question (1) . 2 This data may be used as follows: 5.1.1 For input into static/dynamic analyses; 5.1.2 For computing shear modulus, Young's modulus, and Poisson's ratio (provided density is known or assumed); 5.1.3 For determining Seismic Site Class using the appropriate Building Code; and 5.1.4 For assessing liquefaction potential. 5.2 Fundamental assumptions inherent in the test methods are as follows: 5.2.1 Horizontal layering is assumed. 5.2.2 Snell’s law of refraction applies to P-waves and S-waves and to the velocities derived from crosshole tests. If Snell’s law of refraction is not considered in the analysis of Crosshole seismic testing data, the report shall so state, and the P-wave and S-wave velocities obtained may be unreliable for certain depth intervals near changes in stratigraphy (2) . Note 1 — The quality of the results produced by these test methods is dependent on the competence of the personnel performing it and the suitability of the equipment and facilities. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection and so forth. 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.