1.1 The procedures and methods described in this practice concern the measurement of axial strain and compression (or tension) within a single, vertical deep foundation when loaded in static axial compression or tension. These procedures and methods apply to all deep foundations, referred to herein as piles, that function in a manner similar to driven piles, cast-in-place piles, or barrettes, regardless of their method of installation. This practice would also be applicable to piles not subjected to active test loading (passive monitoring of strain and compression over time in a pile loaded by a structure). Measurement of compression and strain within a pile under lateral load is beyond the scope of this practice. NOTE 1-Compression and tension may be used interchangeably herein. Compression may generally be understood to mean compression or tension. Compressive load may generally be understood to mean compressive or tensile load. Procedures specific to compression measurements may be assumed to be similar or equivalent to procedures specific to tension measurements. 1.2 This practice provides requirements, procedures, and recommendations for proper installation and use of strain and compression detection devices (instrumentation) within deep foundation piles. 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 which involves measurement of compression and strain. 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 this practice. 1.3 Instrumentation 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. 1.4 A qualified engineer shall design and approve the pile instrumentation configuration. The text of this practice references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the practice. This practice also includes illustrations and appendices intended only for explanatory or advisory use. 1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026. 1.6 The method used to specify how data are collected or recorded in this practice is not directly related to the accuracy to which the data can be applied in design or other uses, or both. How one applies any results obtained using this practice is beyond its scope. 1.7 ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this practice. Users of this practice 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. 1.8 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 practice to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
Keywordscompression; tension; strain; pile load testing; bidirectional testing; pile monitoring; field:measurements
The author and his employer has extensive experience with the way in which engineers and practitioners specify strain and compression measurements in deep foundation elements. This experience has shown that there is substantial variability in practices and many incorrect procedures. An ASTM practice--properly approved--would aid the industry in adding consistency and proper techniques.
The title and scope are in draft form and are under development within this ASTM Committee.Back to Top
Draft Under Development