ASTM D2850-23 pdf download – Standard Test Method For Unconsolidated-Undrained Triaxial Compression Test On Cohesive Soils.
1.1 This testing procedure is designed to assess the strength and stress-strain characteristics of cylindrical soil specimens that can be either in a natural state, compacted, or reconsolidated. These specimens are tested under a confining fluid pressure within a triaxial testing apparatus, with no drainage allowed during the application of the confining pressure or during the compression phase. The specimens are loaded axially at a constant rate of axial deformation, which is strain-controlled.
1.2 The method offers data necessary for evaluating the undrained strength properties and stress-strain relationships of soils. It allows for the measurement of total stresses on the specimen without accounting for pore-water pressure corrections.
NOTES:
- Note 1: The unconfined compressive strength of cohesive soils is determined by Test Method D2166/D2166M.
- Note 2: The consolidated, undrained strength of cohesive soils with pore pressure measurement is determined by Test Method D4767.
1.3 All measured and calculated values must adhere to the guidelines for significant digits and rounding as outlined in Practice D6026.
1.3.1 The methods employed for collecting, recording, or calculating data in this standard are considered industry norms. They represent the typical significant digits that are generally retained. These methods do not account for material variability, the purpose of data collection, specific studies, or the user’s objectives. It is customary to adjust the significant digits of reported data to match these considerations. The standard does not address the significant digits used in analysis methods for engineering design.
1.4 Units – The values stated in SI units are to be considered the standard. The values provided in parentheses are conversions to inch-pound units, which are included for informational purposes only and are not considered standard. Reporting test results in units other than SI is not considered non-compliant with this test method.
1.4.1 The inch-pound units conversion employs the gravitational system, where the pound-force (lbf) is a unit of force (weight), and the mass unit is slugs. The slug unit is not specified unless dynamic calculations (F = ma) are required.
