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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Two alternative procedures are provided as follows: However, the time rate of deformation is very sensitive to degree ashm saturation and caution must be exercised regarding estimates for duration of settlements when partially saturated conditions prevail.
Agencies that meet the criteria of Practice D generally are considered capable of competent and objective testing. Combining values from the two systems may result in non-conformance with the standard.
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.
Active view current version of standard. Reliable testing depends on many factors, and Practice D provides a means of evaluation some of these factors. Traditionally, the load duration is the same for each increment and equal to 24 h. Load increment ratios of less than 1 may be desirable for soils that are highly sensitive or whose response is highly dependent on strain rate. 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.
Alternatively, the requesting agency may specify Test Method B wherein the time-deformation readings are taken on all load increments. For some soils, the rate of consolidation is such that complete consolidation dissipation of excess pore pressure will d243 more than 24 h. This implicitly combines two separate systems of units, that is, the absolute system and the gravimetric system.
Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are d245 provided as part of the standard. Two alternative procedures are provided as follows:. These test methods specify procedures for two techniques Method A and Method Bhowever alternative techniques may be used when agreed to by the requesting agency and still be in conformance with these test methods. Alternatively, the requesting agency may specify Test Method B wherein the time-deformation readings are taken on all load increments.
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. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Most intact samples taken from below the water table will be saturated. Work Item s – proposed revisions of d24435 standard.
Estimates of this type are of key importance in the design of engineered structures and the evaluation of their performance. Time-deformation readings are required on a minimum of two load increments. 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 to a sufficiently high stress level.
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.
How one applies the results obtained using this standard is beyond its scope. The required maximum stress level depends on the purpose of the test and must be agreed on with the requesting agency.
It is necessary to use an asttm technique which indirectly determines that consolidation is essentially complete. This test method provides only the compression curve of the specimen and the results combine both primary consolidation and secondary compression deformations.
Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard. Tests performed on other unsaturated materials such as compacted and residual weathered or chemically altered soils may require special evaluation techniques. The values stated in inch-pound units are approximate and given for guidance only.
Consolidation test results are dependent upon the duration of each load increment.
It is d2453 undesirable to combine two separate systems within a single standard. 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. Users of this test method are cautioned that compliance with Practice D does not assure reliable testing. The addition of back pressure saturation does not constitute non-conformance to these test methods. The compressibility of soil particles astj pore water is negligible compared to the compressibility of the soil skeleton.
Alternatively, the test may be performed using an apparatus equipped to saturate the specimen.
Note 2—Time-deformation readings are required to determine the time for completion of primary consolidation and for evaluating the coefficient of consolidation. Reporting of test results in units other than SI shall not be regarded as nonconformance with this test method.
Link to Active This link axtm always route to the current Active version of the standard. Tests performed on other soils such as compacted and residual weathered or chemically altered soils may require special evaluation techniques. 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.
Note 1—The determination of the atsm and magnitude of consolidation of soil when it is subjected to controlled-strain loading is covered by Test Method D In particular, the rate of consolidation interpretation of the time curves is only applicable to fully saturated specimens.
This implicitly combines two separate systems of units, that is, the absolute system and the gravimetric system. The apparatus in general use does not have provisions for formal verification of pore pressure dissipation. In the absence of specific instructions, Section 11 provides the default load increment and load duration schedule for a standard test.