1、Designation:D445214Standard Practice forX-Ray Radiography of Soil Samples1This standard is issued under the fixed designation D4452;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses ind
2、icates the year of last reapproval.Asuperscript 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 cores by X-rayradiography.1.2 This practice enables the user
3、 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 cores(or observetheir features on a fluoroscope)in thin wall tubes or linersranging from approximatel
4、y 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 6 mm(14in.),large lump
5、s 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 or sand seams,narrow
6、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 of extruded cores,ascompared to samples in metal tubes.The method use
7、d forX-raying cores is the same as that for tubes and liners,exceptthat extruded cores have to be handled with extreme care andhave to be placed in sample holders(similar to Fig.2)beforeX-raying.This practice should be used only when natural watercontent or other intact soil characteristics are irre
8、levant to theend 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 obtainedor already tested speci
9、mens be X-rayed.1.5 This practice can only be used to their 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 SI units are to be regardedas standard.The values given in parentheses are
10、 mathematicalconversions to inch-pound units,which are provided forinformation only and are not considered standard.1.6.1 Reporting of test results in units other than SI shall notbe regarded as nonconformance with this test method.1.7 This practice offers a set of instructions for performingone or
11、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 standard of care by whichthe a
12、dequacy 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 process.1.8 All observed and calcu
13、lated 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 significantdigits in the spe
14、cified 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 not consider material variatio
15、n,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 consider significant digits
16、 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 July 1,2014.Published August 2014.Originallyapproved in 1985.Last previous edition approved in 2006 as D4452 06.DOI:10.1520/D4452-14.*