1、Designation: D 5079 02 (Reapproved 2006)Standard Practices forPreserving and Transporting Rock Core Samples1This standard is issued under the fixed designation D 5079; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of las
2、t revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 These practices cover the preservation, transportation,storage, cataloging, retrieval, and post-test disposition of roc
3、kcore samples obtained for testing purposes and geologic study.1.2 These practices apply to both hard and soft rock, butexclude ice and permafrost.1.3 These practices do not apply to those situations in whichchanges in volatile gas components, contamination of the porefluids, or mechanical stress re
4、laxation affect the intended usefor the core.1.4 This practice offers a set of instruction for performingone or more specific operations. This document cannot replaceeducation or experience and should be used in conjunctionwith professional judgement. Not all aspects of this practicemay be applicabl
5、e in all circumstances. This ASTM standard isnot intended to represent or replace the standard of care bywhich the adequacy of a given professional service must bejudged, nor should this document be applied without consid-eration of a projects many unique aspects. The word “Stan-dard” in the title o
6、f this document means only that thedocument has been approved through the ASTM consensusprocess.1.5 This standard does not purport to address the safetyproblems associated with its use. It is the responsibility of theuser of this standard to establish appropriate safety and healthpractices and deter
7、mine the applicability of regulatory limita-tions prior to use.2. Referenced Documents2.1 ASTM Standards:2D 420 Guide to Site Characterization for Engineering De-sign and Construction PurposesD 653 Terminology Relating to Soil, Rock, and ContainedFluidsD2113 Practice for Rock Core Drilling and Sampl
8、ing ofRock for Site InvestigationD 4220 Practices for Preserving and Transporting SoilSamples2.2 API Standard:API RP-40 Recommended Practice for Core Analysis Pro-cedure33. Terminology3.1 Definitions of Terms Specific to This Standard: SeeTerminology D 653 for general definitions.3.2 Definitions of
9、Terms Specific to This Standard:3.2.1 critical caresamples which are fragile or fluid ortemperature sensitive. This protection level includes the re-quirements prescribed for routine and special care.3.2.2 routine carenon-sensitive, non-fragile samples forwhich only general visual identification is
10、necessary, andsamples which will not change or deteriorate before laboratorytesting.3.2.3 soil-like carematerials which are so poorly consoli-dated that soil sampling procedures must be employed toobtain intact pieces of core.3.2.4 special carefluid sensitive samples and those whichmust later be sub
11、jected to testing. Requirements for this levelof protection include those prescribed for routine care.4. Significance and Use4.1 The geologic characteristics and the intended use of therock core samples determine the extent and type of preserva-tion required. If engineering properties are to be dete
12、rmined forthe core, it must be handled and preserved in such a way thatthe measured properties are not significantly influenced bymechanical damage, changes in chemistry, and environmentalconditions of moisture and temperature, from the time that thecore is recovered from the core drill until testin
13、g is performed.Drill core is also the sample record for the subsurface geologyat the borehole location, and as such must be preserved forsome period of time, in some cases indefinitely, for futuregeologic study.4.2 These practices present a selection of curatorial require-ments which apply to the ma
14、jority of projects. The require-ments are given for a variety of rock types and project typesranging from small to large and from noncritical to critical.1These practices are under the jurisdiction ofASTM Committee D18 on Soil andRock and are the direct responsibility of Subcommittee D18.12 on Rock
15、Mechanics.Current edition approved May 1, 2006. Published June 2006. Originallyapproved in 1990. Last previous edition approved in 2002 as D 507902.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandar
16、ds volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American Petroleum Institute, 1220 L Street, Washington, DC20005.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700,
17、 West Conshohocken, PA 19428-2959, United States.Noncritical projects are those in which failure of an element orthe structure would result in negligible risk of injury andproperty loss, while there is great risk to property and life afterfailure of critical structures and projects. Guidance is give
18、n forthe selection of those specific requirements which should befollowed for a given project.5. Guide for Implementation5.1 A qualified person shall be assigned to have curatorialmanagement responsibility for a given project. This personshall be technically competent in the management of rock cores
19、amples and shall have a knowledge of the various end uses forthe cores and their associated preservation requirements. Thisresponsible person shall have the authority to implement therequirements selected from these practices. In some cases, heor she may also have to decide between competing uses fo
20、r thesame core.5.2 The responsible person shall select from Sections 6-11those requirements and procedures that should be applied forthe core from a particular project. The curatorial manager shallthen see that these procedures are implemented, and also seethat the records specified in Section 12 ar
21、e kept.5.3 The following factors should be considered when select-ing the curatorial requirements from Sections 6-11:5.3.1 Project requirements for use of the core range fromsimple ones, in which the only need is to identify and locate thevarious lithologic units, to complex and critical ones in whi
22、chdetailed property testing of the core is required for engineeringdesign. Priorities for multiple uses or different types of testsmust sometimes be established when available core lengths arelimited and when one use or test precludes another. Forexample, splitting a core for detailed geologic study
23、 preventslater strength testing, which requires an intact core.5.3.2 Mechanical property tests for structural design pur-poses should be performed on a core in its natural moisturestate, particularly if the rocks are argillaceous. Irreversiblechanges occur when such rocks are allowed to dry out, oft
24、enresulting in invalid design data. The initial moisture content ofsuch a core should therefore be preserved.5.3.3 Freezing of pore water in the core may reduce thestrength of the rock. The high temperature associated withunventilated storage sheds in summer, and temperatures alter-nating between ho
25、t and cold, may cause moisture migrationfrom the core and weakening of the rock due to differentialthermal expansion and contraction between grains. Such tem-perature extremes should therefore be avoided, particularly forweak sedimentary rock types.5.3.4 A weak rock core may be broken or further wea
26、kenedby careless handling, such as dropping a core box, or bymechanical vibration and shock during transportation. Break-ing of the core reduces sample lengths available for testing.Weakening caused by such mechanical stressing may lowermeasured strength parameters and may affect other properties.5.
27、3.5 The required preservation time may vary from as shortas three months to several years, and sometimes core may needto be stored indefinitely. A core taken simply to identify thebedrock lithology beneath a small structure may be needed fora few months only. For large and critical structures, it ma
28、y benecessary to retain the core for many years as re-examinationand testing may be required at some later time for additionalgeologic study or re-evaluation of property data. Some stateshave regulations governing the disposition and storage of coreobtained within the state.5.4 Fig. 1 is a flow char
29、t that shows the various corehandling, use, and storage activities and the correspondingsection numbers in these practices. Note that four care orprotection levels are defined in Section 3 to account for thegreat variety of rock sensitivities and core uses encountered inpractice.5.5 The person assig
30、ned curatorial management responsibil-ity should study the flow chart in Fig. 1 as it relates to thedesignated Sections 6-11 in these practices. Note in particular,that a selection of the required protection must be made in 7.5,where four levels of protection are specified, namely routinecare, speci
31、al care, critical care, and soil-like care.5.6 Special attention is also directed to records requirementsin Section 12, that document the history of the core handling,preservation, and storage.6. Apparatus6.1 Camera, for taking photographs of cores for logging.6.2 Controlled Humidity Room.6.3 Core B
32、oxesSee 7.6.1.6.4 Vinylidene Chloride Plastic Film, Aluminum Foil, Plas-tic Microcrystalline Wax, for sealing in moisture content ofcores.6.5 Polyethylene Layflat Plastic Tubing.NOTE 1Numbers refer to corresponding sections of this practice.FIG. 1 Flow Chart for Core Handling, Use, and Storage Activ
33、itiesD 5079 02 (2006)26.6 Poly(vinyl chloride) Tubing.6.7 Sawdust, Rubber, Polystyrene, or material of similarresiliency to cushion the core.6.8 Miscellaneous Equipment, such as adhesive tape andwaterproof felt-tip markers.7. Requirements and Procedures at the Drilling Site7.1 Sample Recovery:7.1.1
34、Accomplish sample recovery in accordance with Prac-tice D2113or API RP-40.7.1.2 Whichever approved drilling method is used, removethe samples from the core barrel with a minimum of distur-bance.7.2 Handling:7.2.1 Each borehole shall be given full-time attention by aqualified inspector constantly ava
35、ilable for observing, direct-ing, photographing, and field logging. The inspector shall notperform simultaneously the same duties for more than oneboring unless the borings are close enough to each other so thatthe entire inspection process can be done for each boring.7.2.2 For relatively solid piec
36、es of core that will not beadversely affected, the inspector shall use a marker, such as afelt-tip, to orient each piece so that later users will always beable to distinguish top from bottom. Acceptable formats are acontinuous line with arrows or parallel solid and dashed lineswith the dashed line a
37、lways on the same side of the solid line.The direction convention shall be recorded in the log book.Locations of known depths should be marked directly on thecore when the orientation marks are drawn.7.3 Core Photography:7.3.1 Perform core photography on all core samples with acamera of 35 mm (minim
38、um) format using color film to recordpermanently the unaltered appearance of the rock. The filmselected should be color balanced for the available lighting(daylight, flash, incandescent, or florescent), or an appropriatefilter should be placed on the camera to compensate for thedifference. The core
39、should be cleaned prior to any photogra-phy.7.3.2 A commercially available color strip chart should beincluded in the photo frame to serve as a reference to check theaccuracy of the photographic reproduction of the rock corecolors.7.3.3 For rock placed in core boxes, take one photo of eachbox once i
40、t is filled to capacity. Include the inside of the box lidwith appropriate identification data and a clearly visible lengthscale laid along one edge of the box so that it also shows in thephoto.7.3.4 Where very long, intact cores are being preserved insingle plastic tubes, make detail-revealing clos
41、e-ups of eachcore interval in addition to a single photo showing the completecore.7.3.5 Take photographs before the core is obscured byprotective sealants and wraps, and before any deteriorationbegins in particularly fragile or sensitive rock types.7.3.6 For a boxed core that is not particularly sen
42、sitive andfor which maintenance of in situ moisture content is notimportant, two photos should be made: one with the core in asurface dry condition and one with the core in a wet conditionto bring out optical properties that would not otherwise beapparent.7.3.7 This procedure may require photography
43、 both in thefield and then later in the storage facility, but it must becompleted before any test core removal and before damagefrom mishandling has a chance to occur.7.3.8 Where it is impossible for a photo to show identifica-tion data marked directly on the sample or its container, thenmount appro
44、priately marked placards so as to be included inthe frame.7.3.9 Organize the photographs and mount in a folder foreasy access and preservation.7.4 Initial Logging:7.4.1 The boring inspector must complete at least a prelimi-nary field log of the core before it is packed away to betransported. Suggest
45、ed procedures for logging are given in theliterature.4, 5, 6, 7The preliminary log must include all identi-fication data for the borehole and personnel and equipmentinvolved, notations of coring run depths, recovery percentages,lithologic contact depths, types and locations of protectionapplied to s
46、amples, and any facts that would otherwise beunknown to whomever may complete a more detailed log at alater time. It is desirable that detailed logs be completed by thesame inspector who does the field logging. It is advisable forthe inspector immediately to make notations on the depths atwhich, in
47、his judgment, any core losses occurred. Sometimes itis possible later to fill in gaps in the initial log by interpreta-tions from wireline logs.7.4.2 The inspector is to complete a detailed log on the drillsite (see the literature4, 5, 6, 7) in cases where the core is likelyto deteriorate or otherwi
48、se change before being examinedagain.7.4.3 For fragile core that must be immediately protected bywrapping and sealing, preliminary logging should take place inthe field, but application of protective measures are to takeprecedence over time-consuming detailed logging.NOTE 1It is permissible later to
49、 make changes in detailed logs whenlaboratory analysis indicates original misidentification of rock type orother geologic features.7.5 Sample ProtectionFour levels of sample protectionare covered (see Section 3): routine care, special care, criticalcare, and soil-like care. The level of protection chosen willdepend on the geologic character of the rock and the intendeduse for the core.7.5.1 Routine care (see Fig. 2):4Association of Engineering Geologist, Core Logging Committee, South AfricaSection, “A Guide to Core Logging for Rock Engineering,” Bulletin of theAssociation of
