ASTM International

Standard Practices for Obtaining Intact Block (Cubical and Cylindrical) Samples of Soils
 N D7015

Annotation

These practices outline the procedures for obtaining intact block (cubical and cylindrical) soil samples.

Intact block samples are obtained for laboratory tests to determine the strength, consolidation, permeability, and other geotechnical engineering or physical properties of the intact soil.

Two sampling practices are presented. Practice A covers cubical block sampling, while Practice B covers cylindrical block sampling.

These practices usually involve test pit excavation and are limited to relatively shallow depths. Except in the case of large diameter (that is, greater than 3 4 m) bored shafts of circular cross-section in unsaturated soils, for depths greater than about 1 to 11 2 metres or depths below the water table, the cost and difficulties of excavating, cribbing, and dewatering generally make block sampling impractical and uneconomical. For these conditions, use of a thin-walled push tube soil sampler (Practice D1587), a piston-type soil sampler (Practice D6519), or Hollow-Stem Auger (Practice D6151), Dennison, or Pitcher-type soil core samplers, or freezing the soil and coring may be required. These practices do not address environmental sampling; consult Guides D6169 and D6232 for information on sampling for environmental investigations.

Successful sampling of granular materials requires sufficient cohesion, cementation, or apparent cohesion (due to moisture tension (suction)) of the soil for it to be isolated in a column shape without undergoing excessive deformations. Additionally, care must be exercised in the excavation, preservation and transportation of intact samples (see Practice D4220, Group D).

The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.