1.1 These test methods measure the axial deflection of a single, vertical deep foundation when loaded in bi-directional static axial compression using a specialized jack (or jacks) embedded within the foundation. These test methods apply to all deep foundations, referred to herein as piles, which function in a manner similar to driven piles, cast-in-place piles, or barrettes, regardless of their method of installation. The test results may not represent the long-term performance of a deep foundation. 1.2 These test methods provide minimum requirements for testing deep foundations under bi-directional static axial compressive load. Plans, specifications, and/or provisions prepared by a qualified engineer may provide additional requirements and procedures as needed to satisfy the objectives of a particular test program. The engineer in responsible charge of the foundation design, referred to herein as the Engineer, shall approve any deviations, deletions, or additions to the requirements of these test methods. 1.3 These test methods allow the following test procedures: Procedure A Quick Test, 8.1.2 and Procedure B Extended Test (optional), 8.1.3. 1.4 Apparatus and procedures herein designated optional may produce different test results and may be used only when approved by the Engineer. The word shall indicates a mandatory provision and the word should indicates a recommended or advisory provision. Imperative sentences indicate mandatory provisions. 1.5 A qualified geotechnical engineer should interpret the test results obtained from the procedures of these test methods so as to predict the actual performance and adequacy of piles used in the constructed foundation. See Appendix X1 for comments regarding some of the factors influencing the interpretation of test results. 1.6 A qualified engineer shall design and approve the load test configuration and test procedures. The text of these test methods reference notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of these test methods. These test methods also include illustrations and appendices intended only for explanatory or advisory use. 1.7 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 nonconformance with the standard. 1.8 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 slugs. The rationalized slug unit is not given, unless dynamic (F = ma) calculations are involved. 1.9 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026. 1.10 The method used to specify how data are collected, calculated, or recorded in these test methods 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 these test methods is beyond its scope. 1.11 ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in these test methods. Users of these test methods are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility. 1.12 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.
The bi-directional load test has become the test method of choice for high-capacity load testing around the world. The specific method is currently not described in any standard that is known.
Keywordsfield testing; bi-directional load test; embedded jack; loading procedure; axial static pile capacity; reference beam
The title and scope are in draft form and are under development within this ASTM Committee.Back to Top
Draft Under Development