Standard Test Method for One-Dimension Consolidation Properties of Soil Using Incremental Loading. GeoTesting Express is a provider of Soil Testing Services – ASTM D, Standard Test Method for One-Dimensional Consolidation Properties of Soils. Buy ASTM D TEST METHODS FOR ONE-DIMENSIONAL CONSOLIDATION PROPERTIES OF SOILS USING INCREMENTAL.
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Evaluation techniques specified in these test methods assume the pore space is fully saturated and are generally applicable to soils naturally sedimented in water. The interpretation method specified by these test methods to estimate the preconsolidation stress provides a simple technique to verify that one set of time readings are taken after the preconsolidation stress and that the specimen is loaded atm a sufficiently high stress level.
The apparatus in general use does not have provisions for formal verification of pore pressure dissipation. Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard.
It is scientifically undesirable to combine two astk systems within a single standard. Reliable testing depends on many factors, and Practice D provides a means of evaluation some of these factors. How one applies the results obtained using this standard is beyond its scope. The extent to which partial saturation influences the test results astn be a part of the test evaluation and may include application of theoretical models adtm than conventional consolidation theory.
In the absence of specific instructions, Section 11 provides the default load increment and load duration schedule for a standard test.
Combining values from the two systems may result in non-conformance with the standard. Tests performed on other unsaturated materials such as compacted and residual weathered or chemically altered soils may require special evaluation techniques. This implicitly combines two separate systems of units, that is, the absolute system and the gravimetric system. Work Item s – proposed revisions of this standard.
This test method has been written using SI units; however, inch-pound conversions are given in the gravimetric system, where the pound lbf represents a unit of force weight. For some soils, the rate of consolidation is such that complete consolidation dissipation of excess pore pressure will require more than 24 h.
Alternatively, the test may be performed using an apparatus equipped to saturate the specimen. Other loading astmm may be used to model particular field conditions or meet special requirements.
Consolidation test results are dependent on the magnitude of the load increments. Asgm Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard. Note 2—Time-deformation readings are required to determine the time for completion of primary consolidation and for evaluating the coefficient of consolidation, c v.
Two sstm procedures are provided as follows:. Time-deformation readings are required on a minimum of two load increments. Time-deformation readings are required on a minimum of two load increments.
Estimates of this type are of key importance in the design of engineered structures and the evaluation of their performance. Since c v varies with stress level and loading type loading or unloadingthe load increments with timed readings must be selected with specific reference to the individual project. How one applies the results obtained using this standard is beyond its scope.
Note 1—The determination of the rate and magnitude of consolidation of soil when it is subjected to controlled-strain loading is covered by Test Method D Work Item s – proposed revisions of this standard. Alternatively, the requesting agency may specify Test Method B wherein the time-deformation readings are taken on all load increments. Since c varies with stress level and load increment loading or unloadingthe load increments with timed readings must be selected with specific reference to the individual project.
Users of this test method are cautioned that compliance with Practice D does not assure reliable testing. This test method provides the compression curve with explicit data to account for secondary compression, the coefficient of consolidation for saturated materials, and the rate of secondary compression.
ASTM D Standard
Consolidation test results are dependent upon the duration of each load increment. Reporting of test results in units other than SI shall not be regarded as nonconformance with this test method.
Two alternative procedures are provided as follows:. Note 1—The determination of the rate and magnitude of consolidation of soil when it is subjected to controlled-strain loading is covered by Test Method D These test methods use conventional consolidation theory based on Terzaghi’s consolidation equation to compute the coefficient of consolidation, c v. Two alternative procedures are provided as follows: The apparatus in general use for these test methods do not have provisions for verification of saturation.
Link to Active This link will c2435 route to the current Active version of the standard. It is necessary to use an interpretation technique which indirectly determines that consolidation is essentially complete. Traditionally, dd2435 load duration is the same for each increment and equal to 24 h.
The data from the consolidation test are used to estimate the magnitude and rate of both differential and total settlement of a structure or earthfill. The addition of back pressure saturation does not constitute non-conformance to these test methods.
Note 2—Time-deformation readings are required to determine the time for completion of primary consolidation and for evaluating the coefficient of consolidation. This test method has been written using SI units; however, inch-pound conversions are given in the gravimetric system, where the e2435 lbf represents a unit of force weight. However, the time rate of deformation is very sensitive to degree of saturation and caution must be exercised regarding estimates for duration of settlements when partially saturated conditions prevail.
Inundation of the test specimen does not significantly change the degree of saturation of the test specimen but rather provides boundary water to eliminate negative pore pressure associated with sampling and prevents evaporation during the test.