1、Designation:D4452/D4452M22Standard Practice forX-Ray Radiography of Soil Samples1This standard is issued under the fixed designation D4452/D4452M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.A number in p
2、arentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This practice covers the determination of the quality ofsoil samples in thin wall tubes or of extruded soil cores byX-ray radiography.1.2 This practi
3、ce enables the user to determine the effects ofsampling and natural variations within samples as identified bythe extent of the relative penetration of X-rays through soilsamples.1.3 This practice can be used to X-ray soil cores(or observetheir features on a fluoroscope)in thin wall tubes or linersr
4、anging from approximately 50 to 150 mm 2 to 6 in.indiameter.X-rays of samples in the larger diameter tubesprovide a radiograph of major features of soils anddisturbances,such as large scale bending of edges of varvedclays,shear planes,the presence of large concretions,silt andsand seams thicker than
5、 6 mm 14in.,large lumps of organicmatter,and voids or other types of intrusions.X-rays of thesmaller diameter cores provide higher resolution of soil fea-tures and disturbances,such as small concretions(3 mm 18in.diameter or larger),solution channels,slight bending ofedges of varved clays,thin silt
6、or sand seams,narrow solutionchannels,plant root structures,and organic matter.TheX-raying of samples in thin wall tubes or liners requiresminimal preparation.1.4 Greater detail and resolution of various features of thesoil can be obtained by X-raying extruded soil cores,ascompared to samples in met
7、al tubes.The method used forX-raying soil cores is the same as that for tubes and liners,except that extruded cores have to be handled with extremecare and have to be placed in sample troughs(similar to Fig.2)before X-raying.This practice should be used only whennatural water content or other intact
8、 soil characteristics areirrelevant to the end use of the sample.1.4.1 Often it is necessary to obtain greater resolution offeatures to determine the propriety of sampling methods,therepresentative nature of soil samples,or anomalies in soils.This practice requires that either duplicate samples be o
9、btainedor already tested specimens be X-rayed.1.5 This practice can only be used to its fullest extent afterconsiderable experience is obtained through many detailedcomparisons between the X-ray image and the sample X-rayed.1.6 UnitsThe values stated in either SI units or inch-pound units presented
10、in brackets are to be regarded sepa-rately as standard.The values stated in each system may not beexact equivalents;therefore,each system shall be used inde-pendently of the other.Combining values from the two systemsmay result in nonconformance with standard.1.7 This practice offers a set of instru
11、ctions for performingone or more specific operations.This document cannot replaceeducation or experience and should be used in conjunction withprofessional judgment.Not all aspects of this practice may beapplicable in all circumstances.This ASTM standard is notintended to represent or replace the st
12、andard 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 aspects.The word“Standard”in thetitle of this document means only that the document has beenapproved through the ASTM consensus proces
13、s.1.8 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D6026.1.8.1 For purposes of comparing,a measured or calculatedvalue(s)with specified limits,the measured or calculatedvalue(s)shall be rounded to the nearest decimal or
14、significantdigits in the specified limits.1.8.2 The procedures used to specify how data are collected/recorded or calculated,in this standard are regarded as theindustry standard.In addition,they are representative of thesignification digits that generally should be retained.Theprocedures used do no
15、t consider material variation,purpose forobtaining the data,special purpose studies,or any consider-ations for the users objectives;and it is common practice toincrease or reduce significant digits of reported data to becommensurate with these considerations.It is beyond the scopeof this standard to
16、 consider significant digits used in analysismethods for engineering design.1.9 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is the1This practice is under the jurisdiction of ASTM Committee D18 on Soil andRock and are the direct responsibility of Subcommittee D18.07 on Identification andClassification of Soils.Current edition approved Oct.1,2022.Published October 2022.Originallyapproved in 1985.Last previous edition approved in 2014 as D44
