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~~pu• u oyo
<br />ich can be sccurclt Inckrd tu~_ri h~•r iu (arm
<br />-ylinder meeting the rcyuiruments of Chi,
<br />tion. The molds mar ;d,o he the `taper"
<br />x. providing the internal diameter taper is
<br />form and is not more than Q?00 in.llinear
<br />(16.7 mm/linear m) n( mold heicht. Each
<br />Id shall have a hose plate :nsembh and an
<br />ension collar ^uembly. both made u( rigid
<br />-Cal and constructed so thcs c;m he Brea re lc
<br />ached w or detached fnnn the mold. The
<br />temion mlLv ^ssgmhh ,hall h;ivc a height
<br />tending ahave the top u( the mold of at
<br />w ? in. (?0 F mm). tvhtch milt includr an
<br />per section than Ilares out to form :, funnel
<br />ovided them is m Ica,( a '!,-tn. (19-mm)
<br />night cylindriatl section hrncath it
<br />3.1.1 Mnlrl. 4.0 m. (101.6 mm) in diamc~
<br />r, having a capacity a('/tux 0.0004 (t' (943
<br />l l cm") and conform ing to Fie. I
<br />3.1.2 Mold, 6.0 in. (152.4 mm) in dtameter,
<br />ruing a capacity of vta.~ar t 0.0009 ft' (2124
<br />25 cm') and conforming to Fig. 2.
<br />.'>.1 3 The average inlet nal diametci.
<br />eight. and volume of arch mold sh;dl he
<br />etermmed before initial use and at interval,
<br />u exceeding 1000 times the mold is filled.
<br />he mold volume shall hr calculated from the
<br />vc race of at Ica,t sex internal diameter and
<br />irce hci_chl mca,uremcnn made a, thr near-
<br />,( (1.(1111 in. (11.11? mm). of front Ihr amount
<br />f w;ncr rcyuucd to a+mplctch fill tha mold.
<br />,rrected for tempt rotate van;mce in aceotd-
<br />nce with Table I. I( the uvc r^ee internal
<br />iumeter and volume arc nut ss ohm the ml~
<br />toners shown in Fig,. I or '_, the mold shall
<br />rn be used The determined nilumc ,hall be
<br />,cd m computing the revolved de n,itics.
<br />t ? Runrnter-The rtmmci may he either
<br />tanually operated (see 3.2.1) or mech.mi-
<br />ally operated (see 3.2.2). The rammer shall
<br />all freely through a distance of 12.0 x 'tin in.
<br />304.8 '_ 1.6 mm) (rum the surface of the
<br />pecimen. The manufactured weight of the
<br />ammer shall be 5.5 x OA2 Ib (2.49 x 0.01
<br />;g). The specimen contact face shall be (lat.
<br />3.2.1 Manua! Ramzner-The specimen con-
<br />act face shall be circular with a diameter of
<br />!.000 ~ 0.005 in. (50.80 t 0.13 mm). The
<br />:atttmer shall be equipped with a guide-
<br />sleeve which shall provide sufficient clearance
<br />:o that the free fall oC the rammer shaft and
<br />head will not be restricted. The guidesleeve
<br />shall have four vent holes at each end (eight
<br />holes total) located with centers y~ ± 4~e in.
<br />(19.0 ± 1.6 mm) from each end and spaced 90
<br />deg apan. The minimum diameter of the vent
<br />holes shall be 1'e in. (9.5 mm).
<br />3.?.? ,t1erhaniad Ranurter-The rammer
<br />shall operate mechanicalk in such a manner
<br />m to provide uniform and complete coverage
<br />of the specimen surface. There shall be U.10
<br />0,03 in. (2.S x 0 8 mm)clearance beneeen
<br />the rammer ;md the inside <urfucc of the mold
<br />^t n, ,mallc,t diameter. When used with thr
<br />3.0-in. (101 6-mm) mold. the specimen a>m
<br />fact fatt shall he cucular w~ilh ;, diameter n(
<br />2.000 x 0005 tn. (50.80 x 0.13 mm). When
<br />used with the 6.0-in. (152.4-mm) mold, the
<br />spectmen contact face shall have the shape of
<br />u section of a circle o(a radius equal to 2.90
<br />x 0.02 in. (73.7 x 0 5 mm j. The sector face
<br />rammer shall openue in ouch a manner that
<br />the verses n( the sector is positioned at the
<br />center of the specimen. The mechanical ram-
<br />mer shall he c:d iht:ued and adlusted, e° nec-
<br />esmn~. in aaord;incc with 3.2.3.
<br />3.2.3 Cu6hrorimt and Adju.mnenr -The
<br />mechanical rammer sh:dl be calibrated, and
<br />adlmted a> necessary. before initial use; near
<br />the end of each period during which the mold
<br />tt as filled 1000 times: before reuse otter any-
<br />rhme, includmc npain. which may affect the
<br />tc,t resulh ,ignific^ntls: and whenever the
<br />to>t re,ult, ^ro qucsuonahlc. Each calibration
<br />;md adjustment shall be m accordance with
<br />Method D 2168.
<br />3.3 Snntp/r Etuuder (optional)-A jack,
<br />frame or other device adapted (or the purpose
<br />n( cstruding cam parted spectmem from the
<br />mold.
<br />3 4 Bu/nnre~ -A balance or scale n( at
<br />least 20-kg capacity sensitive to x I g and a
<br />balance of at least 1000-g capacity sensitive
<br />to x0.01 g.
<br />3.5 Drying Oven, thermostatically con-
<br />trolled, preferably of the forced-draft type, ca-
<br />pable of maintaining a temperature of 230 t
<br />9°F (110 t 5°C) for determining the moisture
<br />content of the compacted specimen.
<br />3.6 Straightedge-A stiff metal straightedge
<br />of any convenient length but not less than l0
<br />in. (254 mm). The scraping edge shall have a
<br />straightness tolerance of 10.005 in. (10.13 mm)
<br />and shall be beveled if it is thicker than ye in.
<br />(3 mm).
<br />3.7 Sie,•es. 3-in. (75-mm). '/.-in. (19.0-
<br />202
<br />mm)and Na.4 (4,75-mm). nmform mg to the
<br />requirements of Specification E I 1 .
<br />3.8 Miring Too/s-Miscellaneous tools
<br />such as mixing pan, spoon, trowel, spatula.
<br />etc., or a suitable mechanical device for thor-
<br />oughly mixing the-sample of soil with incre-
<br />ments of water.
<br />4. Procedure
<br />4.1 Specimen Prepnrnrinn -Select a repre-
<br />sentative portion of yu:mtity adeyuatc tit pro-
<br />vide, after sieving. an amount of material
<br />weighing as follows: Method A-2S Ib (I I
<br />kg); Methods 0, C and D-.5(1 Ib (23 ku).
<br />Prepare specimens in accordance with either
<br />4.1 .l through 4.1 .3 or 4.1 .4.
<br />4.1.1 Dry Prepurarion Proa•rlure-If the
<br />sample is too damp to be friable, reduce the
<br />moisture content by drying until the material
<br />is friable; see 4.1 .2. Drying may be in air or
<br />by the use of a drying apparatus such that the
<br />temperature of the sample does not exceed
<br />140°F (60°C ). Alter drying (i( required).
<br />thoroughly break up the aggregations in such
<br />a manner as to avoid reducing the natural size
<br />of the particles. Pass the material through the
<br />specified sieve as (oltows: Methods Aand B -
<br />No. 4 (4.75-mm); Methods C and D-'/<-tn.
<br />(19.0-term). Correct (or oversize material in ac-
<br />cordance with Section 5, if Method D is speci-
<br />fied.
<br />4.1.2 Whenever practicable, soils classified
<br />as ML, CL, OL, GC, SC, MH, CH, OH and
<br />PT by Classification D 2487 shall be prepared
<br />in accordance with 4.1.4.
<br />4.1.3 Prepare a series of at least (our spec
<br />linens by adding increasing amounts of water
<br />to each sample so that the moisture contents
<br />vary by approximately 1 ~/: %. The moisture
<br />contents selected shall bracket the optimum
<br />moisture content, thus providing specimens
<br />which, when Compacted, will increase in mass
<br />to the maximum density and then decrease in
<br />density (see 7.2 :md 7.3 ). Thoroughly mi.a
<br />each specimen to ensure even distribution of
<br />moisture throughout and then place in a sep-
<br />arate covered container and allow to stand
<br />prior to compaction in accordance with Table
<br />2. For the purpose of selecting a standing
<br />.time, it is not required [o perform the actual
<br />classification procedures described in Classi-
<br />fication D 2487 (except in the case of referee
<br />
<br />testing), i( previous data exist which provide
<br />a basis for classifying the sample. `
<br />4.1,4 Moist Prepnrarion Method -The fol-
<br />lowing alternate procedure is recommendAd
<br />(or soils classified as ML. CL, OL. GC, SC,
<br />MH. CH, OH. and PT by Classification
<br />D2487. Without previously drying the sam-
<br />ple, pass it through the '/.-in. (19.0-mm) and
<br />Nu. a (d.75-mm) siex es. Correct for oversize
<br />male nail in accordance with Section 5, i(
<br />Method D is specil icd Prepare a series of al
<br />(cost lour >pectmens hosing moisture contents
<br />that tarv h}' approximately I'/: 4~n. The mms-
<br />nuc conic nls Bela led ,poll hrackcl the npli-
<br />mum muutu rc content. thus proxidmg speci-
<br />mem which, when cum patted, will increase in
<br />mass w the maximum denary ,end then de-
<br />crease in density (see 7 ?and 7.3 ). Tu obtain
<br />the appropriate moisture content of each
<br />specimen, the addition of a predetermined
<br />amount n( water (sec 4.1 .3) ur the removal of
<br />a predclermmcd amount of mo~smre by
<br />drying may be necessary. Drying may be in
<br />air or by the use o(a drying apparatus such
<br />that the temperature o(ttte specimen does not
<br />exceed 140`F (60`C ). The prepared speci-
<br />mens shall then be thoroughly mixed and
<br />Bland. as specified m 4 I .3 and Table 2, poor
<br />m cumpacuun
<br />Nure 1-sanh pracua• n is usually possible to
<br />~~i,ualh pidgc the prim of optimum moisture
<br />closeh enough ,n thin the prepared specimens will
<br />hracket the point of optimum moisture convent.
<br />3.2 Specimen Cumpactinn -Select the
<br />proper compaction mold, m accordance with
<br />the method being used, and attach the mold
<br />extension collar. (:om pact each specimen in
<br />three layers of appro.x+mately equal height.
<br />Each layer shall receive 25 blows in the case
<br />of the 4-tn. (101.6-mm) mold; each layer shall
<br />recetve 56 blows rn the case of the 6-in.
<br />(152.4-mm) mold The total amount of ma-
<br />terial used shall be such that the third com-
<br />pacted laver ra slightly ahoec the top of the
<br />mold. but not exceeding '/. in. (6 mm).
<br />During compaction the mold shall rest on a
<br />uniform rigid foundation, such as provided by
<br />a cylinder or cube of concrete weighing not
<br />less than 200 Ib (91 kg).
<br />4.2.1 In operating the manual rammer,
<br />care shall be taken to axoid rebound of the
<br />rammer from the top end of the guidesleeve.
<br />203
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