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he gwdesleese shall be held ,toady and
<br />ithin 5 deg of the ce rt ital. Apph~ the blow,
<br />a um(orm rate not exceeding approximately
<br />4 s per blow and in such a manner as to
<br />rovide complete voce rage of the specimen
<br />rr(ace.
<br />4.2.2 Following compaction, remove the
<br />xtension collar, carefully trim the compacted
<br />recimen even with the top of the mold by
<br />eons of the straightedge and determine Ote
<br />ass of the specimen. Divide the mass of the
<br />Jmpacled specimen and mold, minus the
<br />ass of the mold, by the volume o! the mold
<br />ee 3.1.3). Record the result as the wet
<br />ensity, yin, in pounds per cubic toot (or
<br />lograms per cubic metre) o(tlie compacted
<br />Jecimen.
<br />4.2.3 Remove the matenal from [hc mold
<br />etermine moisture content in accordance
<br />ith Method D2216, using either the whole
<br />recimen or alternatively a representause
<br />>ecimen of the whole specimen The whole
<br />recimen must be used when the permexbibty
<br />( the compacted specimen is high enough so
<br />at the moisture content is not distributed
<br />niformly throughout. II the whole specimen
<br />used, break it up to facilitate drying. Obtain
<br />e representaYn~e speclmen by dic,ng the
<br />mpacted specimen axially ihnx,gh the cen-
<br />r and remucing IOU to SUU g ul mmcrial
<br />om one o(ttte cut (aces.
<br />4.2A Repeat 4.2 through 4.2.3 (or each
<br />ecimen prepared.
<br />Oversi2e Corrections
<br />5.1 If 30 S'a or more of the sample is
<br />rained on a ih-in. (19.0-mm) sieve. then
<br />ne of the methods described under these
<br />ethods shall be used for the determinaton
<br />either maximum density or optimum mms-
<br />re content.
<br />5.2 Methods A and B-The material re-
<br />ned on the No. 4 (4.75-mm) sieve is dis-
<br />rded and no oversize correction is made.
<br />owever, it is recommended that if the
<br />nouns of material retained is 7 % or greater.
<br />ethod C be used instead.
<br />5.3 Method C-The matenal retained on
<br />e '/a-in. (19.0-mm) sieve is discarded and
<br />oversize correction is made. However, if
<br />e amount of material retained is 10 % or
<br />eater, it is recommended that Method D be
<br />ed instead.
<br />i.4 Method D:
<br />5.4.1 This method shall not be used unless
<br />the amount of material retained on the'l.-in.
<br />(19.0-mm) sieve is 10 9° or greater. When
<br />the amount of material retained on the'/4-in.
<br />sieve is less than 10 %, use Method C.
<br />5 4.2 Pass the material retained on the'/.-
<br />in. (19.0-mm) sieve through a 3-in. or 75-mm
<br />sieve. Discard the material retained on the S-
<br />in. sieve. The material passing the 3-in, sieve
<br />and retained on the '/.-in. sieve shall be
<br />replaced with an equal amount of material
<br />passing a'/.-in. sieve and retained on. a No.4
<br />(4,75-mm) sieve. The material for replace-
<br />ment shall be taken from an unused portion
<br />of the sample.
<br />6. Calculations
<br />6.1 Calculate the moisture content and the
<br />dry density of each compacted specimen as
<br />follows:
<br />w = [(A - B)/(B - Cl] x 100
<br />and
<br />y„ _ [y,,,/(w + 100)] x 100
<br />where:
<br />w =moisture content in percent of the com•
<br />patted specimens,
<br />A = mass of container and moist specimen,
<br />B =mass of container and oven-dried spec
<br />imen,
<br />C =mass oC container,
<br />ye =dry density, in pouods per Cubic foot (et
<br />kilograms per cubic metre) of the com+
<br />patted specimen, and
<br />y,,, =wet density- in pounds per cubic [oqi
<br />(or kilograms per cubic metre) of the
<br />compacted specimen. •7
<br />7. Moisture-Density Relationship
<br />7.1 From the data obtained in 6.1, plot
<br />dry density values as ordinates with co
<br />sponding moisture contents as abscissas. D
<br />a smooth curve connecting the plotted po.
<br />Also draw a curve termed the "curve of c
<br />plete saturation" or "zero air voids curve"
<br />[his plot. This curve represents the relation
<br />between dry density aad cortesponding m
<br />tore contents when the voids ere comple
<br />filled with water. Values of dry density
<br />corresponding moisture contents for plot
<br />the curve of complete saturation caa be c
<br />204
<br />paced using the following equation:
<br />w..,~ _[(62.4/y,J - (l/G.I) x 11)U
<br />where:
<br />w,a, =moisture content in percent tray com-
<br />plete saturation.
<br />y,. = dry density in pounds per cubic fool
<br />(or kilograms per cubic metre).
<br />G, = specific gravity of the material being
<br />tested (see Note 4), and
<br />62.4 =density of water in pounds per cubic
<br />foot (or kilograms per cubic metre).
<br />Nora 4 -The specific gravity of the material can
<br />either be assumed or based on the wcighied averabc
<br />values of: (a) the specific gravity of the material
<br />passing the No. 4 (4.75-mm) sieve in accordance
<br />with Method D 854; and (h) the apparent specific
<br />gravity of the material retained on the Nn. 4 Steve
<br />m accordance wuh Method C 127.
<br />7.2 Optimum Moisture Content, wo-The
<br />' moisture content corresponding to the peak
<br />of the curve drawn as directed in 7.1 shall he
<br />termined the "optimum moisture content."
<br />7.3 Mnximum Density, y,,,;,, -The dry den-
<br />sity in pounds per cubic foot (or kilograms per
<br />cubic metre j of the sample at "optimum mois-
<br />ture content" shall be termed "maximum
<br />density."
<br />g. Report
<br />8.1 The report shall include the following
<br />TABLE I Volume of 4Yaler p<r Crvm bawd nn
<br />Temperature'
<br />Temperatur<.'C (°F) Volume or water. ml/g
<br />t2 (S1.6) I.OOD48
<br />14 (373) 1.00077
<br />Ib (60.8) 1.00103
<br />18 (64.4) 1.00178
<br />20 (68.0) 1.0017'1
<br />22 (71.6) 1.00221
<br />24 (75.1) 1.00268
<br />26 (78.8) 1.00720
<br />28 (82.4) 1.00773
<br />30 (86.D) 1.00473
<br />31 (89.6) 1.00497
<br />" Yalues ocher than shown may be obtained by reierr,ng
<br />the Handbook °/ Chrmivey and Phyrira. Chemical
<br />ihber Publishing Co., CI<veland, Ohio.
<br />205
<br />8 I.I ~4cthud used (Mcthotl A. B. C. or
<br />D ).
<br />8.11 Optimum moisture content.
<br />8.1 .3 Maximum density.
<br />8.1.4 Description of yammer (whether
<br />manual or mechanical).
<br />8.1.5 Description of appearance of mate-
<br />rial used in test, based on Recommended
<br />Practice D 2488 (Classification D 2487 may
<br />be used as an alternative).
<br />8.1 .fi Origin of material used in test.
<br />8.1.7 Preparation procedure used (moist
<br />or dry).
<br />9. Precision
<br />9.1 Criteria for judging the acceptability of
<br />the maximum demity and optimum moisture
<br />content test result, ^re uiven in Table 3. The
<br />standard deviation, s. is calculated (mm the
<br />equation:
<br />n -- 1 J
<br />where:
<br />n =number ofdeterminations,
<br />x =individual value of each determination,
<br />and
<br />z =numerical average of the determinations.
<br />tioro.
<br />9.2 Criteria for cosigning standard devia-
<br />tion values for single-npcrahtt precision are
<br />not available at the present time.
<br />TABLE 2 Dry Prepvratinn M<ihad-SSVnding Tlmes
<br />Classihcation D 2487 Min,mum Sthnding Time,
<br />GW,GP.SW, SP nn requirement
<br />GM,SM J
<br />ML CL. OL. GC. $C IB
<br />MH. CH. OH, Pr J6
<br />
<br />.r
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