ASTM D6236-11

Coring is performed to evaluate construction control and physical properties of stabilized soil.

Coring is conducted to determine the quality and the total thickness of the stabilized soil and to evaluate bonding between lifts.

Coring stabilized soil before it has cured to at least 2100 kPa (300 psi) compressive strength can cause excessive breakage in the core.

If lab-cured specimens are prepared, samples may be cored to correlate with specified break intervals of the lab-cured specimens. Typical curing time intervals are 7, 28, 60, or 90 days or combinations thereof after placement. Twenty-eight (28) days after placement is the most common time interval for first drilling cores.

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 D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard 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.

1.1 This guide covers obtaining cores of soil-cement or lime-stabilized soil for use in determining compressive strength, lift thickness and bond strength, and other physical properties. This guide is primarily for use in coring through shallow (0.3 to 3 m (1 to 10 ft) thick) layers of cement or lime-stabilized soils containing particles < 50 mm (2 in.) in diameter to the underlying foundation.

Note 1—This guide could be used for some Class C self-cementing fly ash materials, which may also stabilize soil.

1.2 This guide does not cover material of less than 2100 kPa (300 psi) compressive strength such as cement-soil-bentonite mixtures or some controlled low strength materials (CLSM).

1.3 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.

1.4 The values stated in SI units are to be regarded as the standard. Other values are examples or for information only.

1.5 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. Specific precautionary statements are given in Section 8.

1.6 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This guide cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this guide may be applicable in all circumstances. This guide 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 guide 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.

1.7 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 as requirements of the standard.