1、Designation: D4546 08D4546 14Standard Test Methods forOne-Dimensional Swell or Collapse of Cohesive Soils1This standard is issued under the fixed designation D4546; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last r
2、evision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 These test methods cover three alternative laboratory methods for measuring free swell, swell pressure, and This standardco
3、vers two laboratory test methods for measuring the magnitude of one-dimensional wetting-induced swell or collapse ofcompacted or intact cohesive soils.unsaturated soils and one method for measuring load-induced compression subsequent towetting-induced deformation.1.1.1 Test Method A is a procedure f
4、or measuring one-dimensional wetting-induced swell or hydrocompression (collapse) ofreconstituted specimens simulating field condition of compacted fills. The magnitude of swell pressure (the minimum verticalstress required to prevent swelling), and free swell (percent swell under a pressure of 1 kP
5、a or 20 lbf/ft2) can also be determinedfrom the results of Test Method A.1.1.2 Test Method B is a procedure for measuring one-dimensional wetting-induced swell or collapse deformation of intactspecimens obtained from a natural deposit or from an existing compacted fill. The magnitude of swell pressu
6、re and free swell canalso be determined from the results of Test Method B.1.1.3 Test Method C is a procedure for measuring load-induced strains on a reconstituted or intact specimen after the specimenhas undergone wetting-induced swell or collapse deformation.NOTE 1Refer to Sections 4, 5, 6 and 13.8
7、 to determine the best method for a particular application.1.2 The test methods can be used to measure the magnitude of one-dimensional wetting-induced In Test Method A, a series ofreconstituted specimens duplicating compaction condition of the fine fraction of the soil in the field (excluding the o
8、versizeparticles) are assembled in consolidometer units. Different loads corresponding to different fill depths are applied to differentspecimens and each specimen is given access to free water until the process of primary swell or collapse (hydrocompression) iscompleted (Fig. 1) under different ver
9、tical (axial) pressures, a constant vertical total stress (Fig. 2). The resulting swell or collapsedeformations are measured. This test method can be referred to as well aswetting-after-loading tests on multiple reconstitutedspecimens. The data from these tests can be used to estimate one-dimensiona
10、l ground surface heave or settlement that can occurdue to full wetting after fill construction. In addition, the magnitude of swell pressure and the magnitude of free swell. It swell canalso be used to obtain data for stress-induced compression following wetting-induced swell or collapse.be interpre
11、ted from the testresults.1.3 Test Method B is commonly used for measuring one-dimensional wetting-induced swell or hydrocompression of individualintact samples. This method can be referred to as single-point wetting-after-loading test. The vertical pressure at wetting for thespecimen is chosen equal
12、 to the vertical in-situ stress (overburden stress plus structural stress, if any) corresponding to the samplingdepth. The test result indicates the amount of heave or hydrocompression that can result when the soil at a given fill depth is wettedfrom the current moisture condition to full inundation
13、 condition. If intact specimens from various depths are tested, the swell orcollapse strain data can be used to estimate heave or settlement of the ground surface. If the objective of the test is to measure swellpressure for an expansive soil, a series of intact specimens from a given depth zone can
14、 be wetted under a range of pressures(similar to Test Method A) and the results interpreted to determine the magnitude of the swell pressure.1.4 Test Method C is for measuring load-induced strains after wetting-induced swell or collapse deformation has occurred. Thismethod can be referred to as load
15、ing-after-wetting test. The test can be performed on either intact or reconstituted specimens, andcan be on one specimen or a series of specimens. The results would apply to situations where new fill, additional structural loads,or both, are applied to the ground that has previously gone through wet
16、ting-induced heave or settlement. The first part of the testis the same as in Test MethodAor B.After completion of the swell or collapse under a given vertical load, additional vertical loadincrements are applied to the specimen in the same manner as in a consolidation test (Test Methods D2435) and
17、the load-inducedstrains are measured.1 These test methods are under the jurisdiction of ASTM Committee D18 on Soil and Rock and are the direct responsibility of Subcommittee D18.05 on Strength andCompressibility of Soils.Current edition approved Oct. 1, 2008March 1, 2014. Published November 2008Apri
18、l 2014. Originally approved in 1985. Last previous edition approved in 20032008as D4546 03.D4546 08. DOI: 10.1520/D4546-08.10.1520/D4546-14.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous
19、version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes
20、section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States11.5 It shall be the responsibility of the agency requesting this test to specify the magnitude of each load for Test Method A andTest Method B.
21、 For Test Method C, the agency requesting the test should specify the magnitude of the stress under which thespecimen is wetted, and the magnitudes of the additional stress increments subsequent to wetting.1.6 These test methods do not address the measurement of soil suction and suction-controlled s
22、well-collapse tests. The additionof suction-controlled wetting does not constitute nonconformance to these test methods.1.7 These test methods have a number of limitations and their results can be affected by one or a combination of factorsincluding the effect of significant amounts of oversize part
23、icles (in Test Method A), sampling disturbance (in Test Method B) anddifferences between the degree of wetting in the laboratory test specimens and in the field. For details of these and other limitations,see Section 6.1.8 UnitsThe values stated in SI units are to be regarded as the standard. The va
24、lues stated in inch-pound units areapproximate.approximate equivalent values provided for information purposes only and are not considered standard. Test resultsrecorded in units other than SI shall not be regarded as nonconformance with this standard. Figures depicting the test results canbe either
25、 in SI units or in inch-pound units.1.8.1 The converted inch-pound units use the gravitational system of units. In this system, the pound (lbf) represents a unit offorce (weight), while the unit for mass is slugs. The slug unit is not given, unless dynamic (F = ma) calculations are involved.1.8.2 It
26、 is common practice in the engineering/construction profession to concurrently use pounds to represent both a unit ofmass (lbm) and of force (lbf). This implicitly combines two separate systems of units; that is, the absolute system and thegravitational system. It is scientifically undesirable to co
27、mbine the use of two separate sets of inch-pound units within a singlestandard. As stated, this standard includes the gravitational system of inch-pound units and does not use/present the slug unit formass. However, the use of balances or scales recording pounds of mass (lbm) or recording density in
28、 lbm/ft3 shall not be regardedas nonconformance with this standard.1.8.3 The terms density and unit weight are often used interchangeably. Density is mass per unit volume whereas unit weightis force per unit volume. In this standard density is given only in SI units. After the density has been deter
29、mined, the unit weightis calculated in SI or inch-pound units, or both.1.9 All measuredobserved and calculated values shall conform to the guidelines for significant digits and rounding establishedin Practice D6026.1.9.1 The methodprocedures used to specify how data are collected, calculated, collec
30、ted/recorded, or recordedcalculated, inthis standard is not directly related to the accuracy to which the data can be applied in design or other uses. How one applies theresults obtained using this standard is beyond its scope.are regarded as the industry standard. In addition, they are representati
31、veof the significant digits that generally should be retained. The procedures used do not consider material variation, purpose forobtaining the data, special purpose studies, or any consideration for the users objectives; and it is common practice to increaseor reduce significant digits of reported
32、data to be commensurate with these considerations. It is beyond the scope of this standardto consider significant digits used in analysis methods for engineering design.1.10 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilit
33、yof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.FIG. 1 Time-Swell CurveD4546 1422. Referenced Documents2.1 ASTM Standards:2C127 Test Method for Density, Relative Density (Specific Gravity), and A
34、bsorption of Coarse AggregateD422 Test Method for Particle-Size Analysis of SoilsD653 Terminology Relating to Soil, Rock, and Contained FluidsD698 Test Methods for Laboratory Compaction Characteristics of Soil Using Standard Effort (12 400 ft-lbf/ft3 (600 kN-m/m3)D854 Test Methods for Specific Gravi
35、ty of Soil Solids by Water PycnometerD1557 Test Methods for Laboratory Compaction Characteristics of Soil Using Modified Effort (56,000 ft-lbf/ft3 (2,700kN-m/m3)D1587 Practice for Thin-Walled Tube Sampling of Soils for Geotechnical PurposesD2216 Test Methods for Laboratory Determination of Water (Mo
36、isture) Content of Soil and Rock by MassD2435 Test Methods for One-Dimensional Consolidation Properties of Soils Using Incremental LoadingD2487 Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System)D2488 Practice for Description and Identification of Soils
37、 (Visual-Manual Procedure)D3550 Practice for Thick Wall, Ring-Lined, Split Barrel, Drive Sampling of SoilsD3740 Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used inEngineering Design and ConstructionD3877 Test Methods for One-Dimensional Exp
38、ansion, Shrinkage, and Uplift Pressure of Soil-Lime MixturesD4220 Practices for Preserving and Transporting Soil SamplesD4318 Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of SoilsD4718 Practice for Correction of Unit Weight and Water Content for Soils Containing Oversize Partic
39、lesD4753 Guide for Evaluating, Selecting, and Specifying Balances and Standard Masses for Use in Soil, Rock, and ConstructionMaterials TestingD6026 Practice for Using Significant Digits in Geotechnical DataE145D6027 Specification for Gravity-Convection and Forced-Ventilation OvensPractice for Calibr
40、ating Linear DisplacementTransducers for Geotechnical Purposes (Withdrawn 2013)3D6913 Test Methods for Particle-Size Distribution (Gradation) of Soils Using Sieve Analysis3. Terminology3.1 DefinitionsRefer to TerminologyFor definitions of D653 for standard definitions of mon technical terms in thiss
41、tandard, refer to Terminology D653.3.2 Definitions of Terms Specific to This Standard:2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary
42、page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.FIG. 2 Deformation versusVersus Vertical Stress, Test Method AD4546 1433.2.1 collapse or hydrocompression, Lhydrocompression (L)wetting-induced decrease in height of a soil element or tests
43、pecimen, specimen.h.3.2.2 collapse or hydrocompression strain%-wetting-induced change in height divided by the height immediately prior towetting, (wetting.h/h) 100.3.2.3 compression, Lcompression (L)decrease in height of a soil element or test specimen, specimen h,due to wetting(synonymous with hyd
44、rocompression or collapse),collapse) or due to increase in total stress.3.2.4 free swell, %percent swell, (swell h/h) 100, following absorption of water at the seating pressure of 1 kPa (20 lbf/ft2).3.2.5 heave (L)increase in vertical height, h, of a column of soil of height h following absorption o
45、f water.3.2.5 intact specimena test specimen obtained from a natural deposit or from an existing compacted fill or embankment usingundisturbed sampling equipment.3.2.6 percent heave or settlement, %change in vertical height divided by the height of a column of soil immediately beforewetting; (wettin
46、g.h/h) 100.3.2.7 primary swell or collapse, Lcollapse (L)amount of swell or collapse characterized as being completed at theintersection of the two tangents to the curve shown in Fig. 1.3.2.8 remolded or compacted reconstituted specimena test specimen compacted into a mold.3.2.9 secondary swell or c
47、ollapse, Lcollapse (L)long-term swell or collapse characterized as the linear portion of the plotshown in Fig. 1 following completion of primary swell or collapse.3.2.10 settlement, Lsettlement (L)decrease in vertical height, height h,of a column of soil of height soil.h.3.2.11 swell, Lswell (L)incr
48、ease in thickness of a soil element or a soil specimen following absorption of water.3.2.12 swell pressure, FLpressure (FL-2)the minimum stress required to prevent swelling.4. Summary of Test Methods4.1 The following three alternative In these test methods require that soil specimens be restrained l
49、aterally a soil specimen isrestrained laterally in a rigid mold and loaded vertically in a consolidometer, with access to free water.(axially) in increments upto a load that depends on the purpose of the test. Subsequent to reaching equilibrium under the applied load, the specimen isinundated with test water and the one-dimensional wetting-induced swell or collapse strain is measured. Test MethodAis specifiedfor specimens that are reconstituted using the fill material excluding the oversize fraction. Test Method B is for intact s
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