ASTM D4083-1989(2016) Standard Practice for Description of Frozen Soils (Visual-Manual Procedure)《描述冻土的标准实施规程 (目视手动程序)》.pdf

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1、Designation: D4083 89 (Reapproved 2016)Standard Practice forDescription of Frozen Soils (Visual-Manual Procedure)1This standard is issued under the fixed designation D4083; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year o

2、f last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This practice presents a proce

3、dure for the description offrozen soils based on visual examination and simple manualtests.1.2 It is intended to be used in conjunction with Test MethodD2487 and Practice D2488, which describe and classify soils,but do not cover their frozen state.1.3 This procedure is based on “Guide to Field Descr

4、iptionof Permafrost for Engineering Purposes,” National ResearchCouncil of Canada, 1963, and MIL-STD-619.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and

5、 health practices and determine the applica-bility of regulatory limitations prior to use.1.5 This practice offers a set of instructions for performingone or more specific operations. This document cannot replaceeducation or experience and should be used in conjunctionwith professional judgment. Not

6、 all aspects of this practice maybe applicable in all circumstances. This ASTM standard is notintended to represent or replace the standard of care by whichthe adequacy of a given professional service must be judged,nor should this document be applied without consideration ofa projects many unique a

7、spects. The word “Standard” in thetitle of this document means only that the document has beenapproved through the ASTM consensus process.2. Referenced Documents2.1 ASTM Standards:2D420 Guide to Site Characterization for Engineering Designand Construction Purposes (Withdrawn 2011)3D653 Terminology R

8、elating to Soil, Rock, and ContainedFluidsD1452 Practice for Soil Exploration and Sampling by AugerBoringsD2487 Practice for Classification of Soils for EngineeringPurposes (Unified Soil Classification System)D2488 Practice for Description and Identification of Soils(Visual-Manual Procedure)2.2 Mili

9、tary Standard:MIL-STD-619 Unified Soil Classification System for Roads,Airfields, Embankments and Foundations43. Terminology3.1 Definitions:3.1.1 Definitions of the soil components of a frozen soilmass, that is, boulders, cobbles, gravel, sand, fines (silt andclay), and organic soils and peat shall

10、be in accordance withTerminology D653.3.1.2 The following terms are used in conjunction with thedescription of frozen ground areas (Fig. 1):53.1.2.1 annual frost zone (active layer)the top layer ofground subject to annual freezing and thawing.3.1.2.2 frost tablethe frozen surface, usually irregular,

11、 thatrepresents the level, to which thawing of seasonally frozenground has penetrated. See Fig. 1.3.1.2.3 frozen zonea range of depth within which the soilis frozen. The frozen zone may be bounded both top andbottom by unfrozen soil, or at the top by the ground surface.3.1.2.4 ground icea body of mo

12、re or less clear ice withinfrozen ground.3.1.2.5 ice wedgea wedge-shaped mass in permafrost,usually associated with fissures in polygons.1This practice is under the jurisdiction of ASTM Committee D18 on Soil andRockand is the direct responsibility of Subcommittee D18.19 on Frozen Soils andRock.Curre

13、nt edition approved June 1, 2016. Published June 2016. Originallyapproved in 1982. Last previous edition approved in 2007 as D4083 83 (2007).DOI: 10.1520/D4083-89R16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual B

14、ook of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from Naval Publications and Forms Center, 5801 Tabor Ave.,Philadelphia, PA 19120.5For more complete

15、lists of generally accepted terms used in the description offrozen ground see: Hennion, F., “Frost and Permafrost Definitions,” Bulletin 111,Highway Research Board, Washington, DC 1955; and Brown, R. J. E., and Kupsch,W. D., “Permafrost Terminology,” Technical Memorandum No. 111, NationalResearch Co

16、uncil of Canada, 1974.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.2.6 icinga surface ice mass formed by freezing ofsuccessive sheets of water.3.1.2.7 permafrostthe thermal condition in soil or rock,wherein the materials have e

17、xisted at a temperature below 0C(32F) continuously for a number of years. Pore fluids or icemay or may not be present.3.1.2.8 permafrost tablethe surface that represents theupper limit of permafrost.3.1.2.9 polygons (polygonal ground)more or less regular-sized surface patterns created by thermal con

18、traction of theground. Two types are common: (a) those with depressedcenters and (b) those with raised centers.3.1.2.10 residual thaw zonea layer of unfrozen groundbetween the permafrost and the annual frost zone. This layerdoes not exist where annual frost extends to permafrost.3.1.3 The following

19、terms are used to describe the charac-teristics of the frozen earth:3.1.3.1 candled iceice that has rotted or otherwise formedinto long columnar crystals, very loosely bonded together.3.1.3.2 clear iceice that is transparent and contains only amoderate number of air bubbles.3.1.3.3 cloudy iceice tha

20、t is translucent or relativelyopaque due to the content of air or for other reasons, but whichis essentially sound and nonpervious.3.1.3.4 excess iceice in excess of the fraction that wouldbe retained as water in the soil voids after thawing.3.1.3.5 friablea condition under which the material iseasi

21、ly broken up under light to moderate pressure.3.1.3.6 granular iceice that is composed of coarse, moreor less equidimensional, crystals weakly bonded together.3.1.3.7 ice coatings on particlesdiscernible layers of icefound on or below the larger soil particles in a frozen soil mass.They are sometime

22、s associated with hoarfrost crystals, whichhave grown into voids produced by the freezing action.3.1.3.8 ice crystala very small individual ice particlevisible in the face of a soil mass. Crystals may be present aloneor in combination with other ice formations.3.1.3.9 ice lenseslenticular ice format

23、ions in soil occur-ring essentially parallel to each other, generally normal to thedirection of heat loss, and commonly in repeated layers.3.1.3.10 ice segregationthe growth of ice within soil inexcess of the amount that may be produced by the in-placeconversion of the original void moisture to ice.

24、 Ice segregationoccurs most often as distinct lenses, layers, veins, and masses,commonly, but not always, oriented normal to the direction ofheat flow.3.1.3.11 poorly bondeda condition in which the soilparticles are weakly held together by the ice so that the frozensoil has poor resistance to chippi

25、ng and breaking.3.1.3.12 porous iceice that contains numerous voids, usu-ally interconnected and usually resulting from melting at airbubbles or along crystal interfaces from presence of salt orother materials in the water, or from the freezing of saturatedsnow. Though porous, the mass retains its s

26、tructural unity.3.1.3.13 thaw stablethe characteristic of frozen soils that,upon thawing, do not show loss of strength in comparison tonormal, long-time thawed values nor produce detrimentalsettlement.3.1.3.14 thaw unstablethe characteristic of frozen soilsthat, upon thawing, show significant loss o

27、f strength incomparison to normal, long-time thawed values or producesignificant settlement, or both, as a direct result of the meltingof excess ice in the soil.3.1.3.15 well bondeda condition in which the soil par-ticles are strongly held together by the ice so that the frozensoil possesses relativ

28、ely high resistance to chipping or break-ing.FIG. 1 Illustration of Frozen Soil TerminologyD4083 89 (2016)24. Significance and Use4.1 This practice is intended primarily for use by geotech-nical engineers and technicians and geologists in the field,where the soil profile or samples from it may be ob

29、served in arelatively undisturbed (frozen) state.4.2 It may also be used in the laboratory to describe thecondition of relatively undisturbed soil samples that have beenmaintained in a frozen condition following their acquisition inthe field.4.3 The practice is not intended to be used in describingu

30、nfrozen soils or disturbed samples of frozen soil.5. Apparatus5.1 Required Apparatus:5.1.1 Pocket knife or small spatula.5.1.2 Low-power magnifying hand lens.5.1.3 Pint-size graduated jars.5.2 Useful Auxiliary Apparatus:5.2.1 Camera.5.2.2 Small bottle of dilute hydrochloric acid.5.2.3 Small test tub

31、e and stopper.5.2.4 Munsell Soil Color Chart or Rock Color Chart, orboth.5.2.5 Thermometer.6. General Procedure for Identification6.1 The system for describing and classifying frozen soil isbased on an identification procedure which involves three stepsdesignated as Parts I, II, and III. Part I cons

32、ists of a descriptionof the soil phase, Part II consists of the addition of soilcharacteristics resulting from the frozen state, and Part IIIconsists of a description of the important ice strata associatedwith the soil.NOTE 1In addition to the description of the soil profile at a given site,it is no

33、rmally advantageous to describe the local terrain features. Particu-larly useful are descriptions of the type of vegetation cover, depth and typeof snow cover, local relief and drainage conditions, and depth of thaw.One or more photos of the area also can be very helpful. The terminologygiven in 3.1

34、.2 should be used to describe any special conditions which canbe recognized. To these should be added any available information on thedepth of thaw as estimated from borings and test pits at the site.7. Part I, Description of the Soil Phase67.1 The soil phase, whether thawed or frozen, is firstdescr

35、ibed in accordance with Practice D2488.8. Part II, Description of the Frozen Soil8.1 Frozen soils in which ice is not visible to the unaidedeye are designated by the symbol N and are divided into twomain subgroups as shown in Fig. 2.8.1.1 Poorly bonded or friable material in which segregatedice is n

36、ot visible to the unaided eye is designated by the symbolNf. This condition exists when the degree of saturation is low.6When the surface soils are mostly organic (peat) a more complete descriptioncan be achieved through use of the “Guide to a Field Description of Muskeg,” I. C.McFarlane, in Special

37、 Procedures for Testing Soil and Rock for EngineeringPurposes, 5th Ed., ASTM STP 479, 1970.NOTE 1Frozen soils in the N group may, on close examination, indicate presence of ice within the voids of the material by crystalline reflections orby a sheen on fractured or trimmed surfaces. The impression r

38、eceived by the unaided eye, however, is that none of the frozen water occupies space inexcess of the original voids in the soil. The opposite is true of frozen soils in the V group.NOTE 2When visual methods may be inadequate, a simple field test to aid evaluation of volume of excess ice can be made

39、by placing some frozensoil in a small jar, allowing it to melt, and observing the quantity of supernatant water as a percentage of total volume.GroupSymbolSubgroupField IdentificationDescription SymbolPoorly bonded or friable NfIdentify by visual examination. To determine presence of excess ice, use

40、 procedure under Note 2and hand magnifying lens as necessary. For soils not fully saturated, estimate degree of icesaturation; medium, low. Note presence of crystals or of ice coatings around larger particles.NNo excess iceWell-bondedExcess iceNbNbnNbeFIG. 2 Description of Frozen SoilsIce Not Visibl

41、eD4083 89 (2016)38.1.2 Well-bonded frozen soil in which the ice cements thematerial into a hard solid mass, but in which segregated ice isnot visible to the unaided eye is designated by the symbol Nb.It may further be described on the basis of detailed examinationand assigned to one of two subtypes.

42、 See Fig. 2.8.1.2.1 If no excess ice is present as indicated by theabsence of segregation even under magnified viewing, thematerial is designated by the symbol Nbn.8.1.2.2 If excess ice is present, but is so uniformly distrib-uted that it is not easily apparent to the unaided eye, thematerial is des

43、ignated by the symbol Nbe. This condition mayoccur in very fine silty sands or coarse silts and can be verifiedby placing some frozen soil in a graduated jar, allowing it tomelt, and observing the quantity of supernatant water as apercentage of the total volume. See Fig. 2.8.2 Frozen soils in which

44、significant segregated ice isvisible to the unaided eye, but individual ice masses or layersare less than 1 in. (25 mm) in thickness are designated by thesymbol V. These are divided into five subgroups as shown inFig. 3.8.2.1 The symbol Vxdesignates those frozen soils whichcontain individual ice cry

45、stals or inclusions. See Fig. 3.8.2.2 The symbol Vcdesignates those frozen soils in whichthe ice occurs as coatings on particles.8.2.3 The symbol Vrdesignates frozen soil masses withrandom or irregularly oriented ice formations.8.2.4 The symbol Vsdesignates that the frozen soil isinterspersed with s

46、tratified or distinctly oriented ice forma-tions.8.2.5 The symbol Vudesignates visible ice, uniformly dis-tributed throughout the soil mass.NOTE 2When more than one subgroup characteristic is present in thesame material, multiple subgroup designations such as Vs,rmay be used.9. Part III, Description

47、 of Substantial Ice Strata9.1 Ice strata that are greater than 1 in. (25 mm) in thicknessare designated by the symbol ICE and divided into twosubgroups as shown in Fig. 4.9.1.1 If the ice stratum contains soil inclusions, it is desig-nated as ICE + Soil Type.9.1.2 If the ice stratum contains no soil

48、 inclusions,itisdesignated simply as ICE.10. Identification of Frozen Soils10.1 Figs. 2-4 also contain information that is helpful indetermining the proper identification of a frozen soil mass. Thevarious items listed which pertain to the ice phase should berecorded whenever applicable.10.2 When gre

49、ater detail and more specific information aredesired than is obtainable from visual inspection, additionalphysical tests and measurements may be performed on thefrozen or thawed soil, or both. These may include in-placeNOTE 1Frozen soils in the N group may, on close examination, indicate presence of ice within the voids of the material by crystalline reflections orby a sheen on fractured or trimmed surfaces. The impression received by the unaided eye, however, is that none of the frozen water occupies space inexcess of the original voids in the so