1、Designation: D 5195 02Standard Test Method forDensity of Soil and Rock In-Place at Depths Below theSurface by Nuclear Methods1This standard is issued under the fixed designation D 5195; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, the year of last 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. Scope1.1 This test method covers the calculation of the density ofsoil and rock by the attenuation of gamma rad
3、iation, where thegamma source and the gamma detector are placed at thedesired depth in a bored hole lined by an access tube.1.2 The density, in mass per unit volume of the materialunder test, is calculated by comparing the detected rate ofgamma radiation with previously established calibration data(
4、see Annex A1).1.3 A precision statement has not been developed for thisstandard at this time. Therefore, this standard should not beused for acceptance or rejection of a material for purchasignpurposes unless correlated to other accepted ASTM standards.1.4 The values stated in SI units are regarded
5、as thestandard. The inch-pound units given in parentheses are forinformation only and may be approximate.1.5 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
6、 health practices and determine the applica-bility of regulatory limitations prior to use. Specific precau-tionary statements are given in Section 6, “Hazards.”2. Referenced Documents2.1 ASTM Standards:D 1452 Practice for Soil Investigation and Sampling byAuger Borings2,3D 1587 Practice for Thin Wal
7、led Tube Sampling of Soils2D2113 Practice for Diamond Core Drilling for Site Inves-tigation2D 2216 Method for Laboratory Determination of Water(Moisture) Content of Soil, Rock, and Soil-AggregateMixtures2D 2922 Test Methods for Density of Soil and Soil-Aggregate In-Place by Nuclear Methods (Shallow
8、Depth)2D 2937 Test Method for Density of Soil In-Place by theDrive-Cylinder Method2D 4428/D4428M Test Method for Crosshole Seismic Test-ing2D 5220 Test Method for Water Content of Soil and RockIn-Place by Downhole Neutron Probe Method43. Significance and Use3.1 This test method is useful as a rapid,
9、 nondestructivetechnique for the calculation of the in-place density of soil androck at desired depths below the surface as opposed to surfacemeasurements in accordance with Test Method D 2922.3.2 This test method is useful for informational and researchpurposes. It should only be used for quality c
10、ontrol andacceptance testing when correlated to other accepted methodssuch as Test Method D 2937.3.3 The non-destructive nature of the test method allowsrepetitive measurements to be made at a single test location forstatistical analysis and to monitor changes over time.3.4 The fundamental assumptio
11、ns inherent in this testmethod are that Compton scattering and photoelectric absorp-tion are the dominant interactions of the gammas and thematerial under test.4. Interferences4.1 The chemical composition of the sample may effect themeasurement and adjustments may be necessary. Some ele-ments with a
12、tomic numbers greater than 20 such as iron (Fe) orother heavy metals may cause measurements higher than thetrue value.4.2 The sample heterogeneity affects the measurements.This test method also exhibits spatial bias in that it is moresensitive to material closest to the access tube.4.2.1 Voids aroun
13、d the access tube can affect the measure-ment (see 8.1.2.1).4.3 The sample volume is approximately 0.028 m3(0.8 ft3).The actual sample volume is indeterminate and varies with the1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subco
14、mmittee D18.08 on Special andConstruction Control Tests.Current edition approved Feb. 10, 2002. Published May 2002. Originallypublished as D 519591. Last previous edition D 519591(1996).2Annual Book of ASTM Standards, Vol 04.08.3Replace with continuous flight and hollowstream methods when available.
15、4Annual Book of ASTM Standards, Vol 04.09.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.apparatus and the density of the material. In general, the greaterthe density the smaller the volume.5. Apparatus (See Fig. 1)5.1 The apparatus
16、 shall consist of a nuclear instrumentcapable of measuring density of materials at various depthsbelow the surface and contain the following:5.1.1 Sealed Source of High Energy Gamma Radiation,such as cesium-137, cobalt-60, or radium-226.5.1.2 Gamma DetectorAny type of gamma detector suchas a Geiger-
17、Mueller tube.5.1.3 Suitable Timed Scaler and Power Source.5.2 Cylindrical ProbeThe apparatus shall be equippedwith a cylindrical probe, containing the gamma source anddetector, connected by a cable of sufficient design and length,that is capable of being lowered down a cased hole to desiredtest dept
18、hs.5.3 Reference StandardThe apparatus shall be equippedwith a reference standard, a fixed shape of dense material usedfor checking apparatus operation and to establish conditions fora reproducible reference count rate. It may also serve as aradiation shield.5.4 Apparatus PrecisionSee Annex A3 for t
19、he precisionof the apparatus.5.5 Accessories:5.5.1 Access TubingThe access tubing (casing) is requiredfor all access holes in nonlithified materials (soils and poorlyconsolidated rock) that cannot maintain constant boreholediameter with repeated measurements. If access tubing isrequired it must be o
20、f a material such as aluminum, steel, orpolyvinyl chloride, having an interior diameter large enough topermit probe access without binding, and an exterior diameteras small as possible to provide close proximity of the materialunder test. The same type of tubing must be used in the field asis used i
21、n calibration.5.5.2 Hand Auger or Power Drilling Equipment, that can beused to establish the access hole. Any drilling equipment thatprovides a suitable clean open hole for installation of accesstubing and insertion of the probe that ensures the measure-ments are performed on undisturbed soil and ro
22、ck whilemaintaining constant borehole diameter shall be acceptable.The type of equipment and methods of advancing the accesshole should be reported.6. Hazards6.1 This equipment utilizes radioactive materials that maybe hazardous to the health of the users unless proper precau-tions are taken. Users
23、of this equipment must become com-pletely familiar with possible safety hazards and with allapplicable regulations concerning the handling and use ofradioactive materials. Effective user instructions together withroutine safety procedures are a recommended part of theoperation of this apparatus.7. C
24、alibration, Standardization, and Reference Check7.1 Calibrate the instrument in accordance with Annex A1.7.2 Adjust the calibration in accordance with Annex A2 ifadjustments are necessary.7.3 Standardization and Reference Check:7.3.1 Nuclear apparatus are subject to the long-term decayof the radioac
25、tive source and aging of detectors and electronicsystems that may change the relationship between count rateand material density. To offset these changes, the apparatusmay be calibrated as the ratio of the measured count rate to acount rate made on a reference standard. The reference countrate shoul
26、d be in the same or a higher order of magnitude thanthe range of measurement count rates over the useful densityrange of the apparatus.7.3.2 Standardization of equipment should be performed atthe start of each days work, and a permanent record of thesedata retained. Perform the standardization with
27、the apparatuslocated at least 10 m (30 ft) away from other apparatuscontaining radioactive sources and clear of large masses orother items which may affect the reference count rate.7.3.2.1 If recommended by the apparatus manufacturer toprovide more stable and consistent results: turn on the appa-rat
28、us prior to use to allow it to stabilize, and leave the power onduring the days testing.7.3.2.2 Using the reference standard, take at least fourrepetitive readings at the normal measurement period anddetermine the mean. If available on the apparatus, one mea-surement at a period of four or more time
29、s the normal periodis acceptable. These measurements constitute one standardiza-tion check.7.3.2.3 If the value obtained above is within the limits statedbelow, the apparatus is considered to be in satisfactory condi-tion and the value may be used to determine the count ratios forthe day of use. If
30、the value is outside these limits, allowadditional time for the apparatus to stabilize, make sure thearea is clear of sources of interference and then conductanother standardization check. If the second standardizationcheck is within the limits, the apparatus may be used, but if italso fails the tes
31、t, the apparatus shall be adjusted or repaired asrecommended by the manufacturer. The limits are as follows:Ns#No 12.0=No=F(1)and:Ns$No 22.0=No=FFIG. 1 Schematic Diagram: Depth Density by Nuclear MethodD5195022where:Ns = value of current standardization check,No = average of the past four values of
32、Ns taken previ-ously, andF = value of prescale (see A3.2.1).7.3.3 If the apparatus standardization has not been checkedwithin the previous three months, perform at least four newstandardization checks and use the mean as the value for No.7.3.4 Use the value of Ns to determine the count ratios forthe
33、 current days use of the apparatus. If for any reason themeasured density becomes suspect during the days use,perform another standardization check.8. Procedure8.1 Installation of Access Tubing (Casing):8.1.1 Drill the access tube hole and install access tube in amanner dependent upon the material t
34、o be tested, the depth tobe tested, and the available drilling equipment.8.1.2 The access hole must be clear enough to allowinstalling the tube yet must provide a snug fit. Voids along sidethe tube will cause erroneous readings.8.1.2.1 If voids are suspected to be caused by the drillingprocess they
35、can be grouted using the procedures in TestMethod D 4428. The only method to determine the presence ofvoids is to perform field calibrations provided in A1.3.8.1.3 Record and note the position of the ground watertable, perched water tables, and changes in strata as drillingprogresses.8.1.3.1 If grou
36、nd water is encountered or saturated condi-tions are expected to develop, seal the tube using proceduresgiven in Test Method D 4428 at the bottom to prevent waterseepage into the tube. This will prevent erroneous readings andpossible damage to the probe.8.1.4 The tube should project above the ground
37、 and becapped to prevent foreign material from entering. The accesstube should not project above the ground so high as it might bedamaged by equipment passing over it.8.1.4.1 Install all tubes at the same height above ground asthis enables marking the cable to indicate the measured depthto be used f
38、or all tubes.8.2 Lower a dummy probe down the access tube to verifyproper clearance before lowering the probe containing theradioactive source.8.3 Standardize the apparatus.8.4 Proceed with the test as follows:8.4.1 Seat the apparatus firmly over the access tube, thenlower the probe into the tube to
39、 the desired depth. Secure theprobe by cable clamps (usually provided by the apparatusmanufacturer).8.4.2 Take a measurement count at the selected timingperiod.NOTE 1The above procedure is performed in an installed access tubethat will allow repeated in-place measurements. In some field situations i
40、tmay be more appropriate to use a drilling technique involving alternatingbetween a large diameter hollow-stem auger, a split-spoon sampler, orthin-walled volumetric sampler and access tubing. This technique isdestructive and only one measurement can be made at each depth per hole.9. Calculation9.1
41、Determine the ratio of the reading obtained compared tothe standard count. Then using the calibration data combinedwith appropriate calibration adjustments, or apparatus directreadout feature, determine the in-place density. This is the bulkor wet density.NOTE 2Some instruments have built-in provisi
42、ons to compute anddisplay the ratio and corrected bulk or wet density per unit volume.9.1.1 If the dry density is required determine the in-placewater content using either gravimetric samples and laboratorydetermination of water content (see Method D 2216), or thesame apparatus or a different appara
43、tus which determines watercontent by the neutron probe method (Method D 5220). Thedry density is calculated by either of the following equations:pd 5pw1 1 M/100(2)or:pd 5 pw 2 Mmwhere:pd = dry density in kg/m3(lbf/ft3),pw = wet density in kg/m3(lbf/ft3),Mm = water density in kg/m3(lbf/ft3) from appa
44、ratus, andM = water as a percent of the dry density from lab.10. Report10.1 Report the following information:10.1.1 Make, model, and serial number of the apparatus,10.1.2 Date of calibration,10.1.3 Method of calibration, such as field, factory, etc.10.1.4 Calibration adjustments,10.1.5 Date of test,
45、10.1.6 Standard count for the day of the test,10.1.7 Any adjustment data for the day of the test,10.1.8 Test site identification including; tube location(s) andtube number(s),10.1.9 Tube type and tube installation methods (methods ofdrilling, installing and any initial gravimetric and count data),10
46、.1.10 Geologic log of the borehole, and10.1.11 Depth, measurement count data, and calculateddensity of each measurement.11. Precision and Bias11.1 PrecisionThe precision of this test method is opera-tor dependent and a function of the care exercised in installingthe access tubing and performing the
47、steps of the proceduresproperly. Interferences as described in Section 4, such as voids,large rocks, and varying densities at different depths of theaccess tube would also prevent developing a meaningfulprecision statement.11.2 BiasNo methods are presently available that providesufficiently accurate
48、 values of density of soil and rock in-placeagainst which this test method can be compared.12. Keywords12.1 depth probe; in-place density; in situ density; nuclearmethodsD5195023ANNEXES(Mandatory Information)A1. CALIBRATIONA1.1 At least once each year, establish or verify calibrationcurves, tables,
49、or equation coefficients by determining by testthe count rate of at least three samples of different knowndensities. This data may be presented in the form of a graph,table, equation coefficients, or stored in the apparatus, to allowconverting the count rate data to material density. The methodand test procedures used in establishing these count ratios mustbe the same as those used for obtaining the count ratios forin-place material. The densities of materials used to establishthe calibration must vary through a range to include the densityof the in-place materials to be t
