1、Designation: D 4013 98 (Reapproved 2005)Standard Practice forPreparation of Test Specimens of Bituminous Mixtures byMeans of Gyratory Shear Compactor1This standard is issued under the fixed designation D 4013; the number immediately following the designation indicates the year oforiginal adoption or
2、, in the case of revision, 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 practice covers the preparation of 10-cm or 4-in.diameter test specimens
3、of bituminous mixturescontaining 22.4-mm (78-in.) aggregate.1.2 The values stated in SI units are to be regarded asstandard.1.3 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 appr
4、o-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E4 Practices for Force Verification of Testing Machines3. Summary of Practice3.1 This practice employs gyratory-shearing action of themixture at low
5、 initial pressures, allowing orientation of theaggregate particles to aid compaction, and then nongyratorycompression at high pressure for consolidation and shaping.4. Significance and Use4.1 The specimens are compacted to simulate the density,aggregate degradation, and structural characteristics po
6、ssible inthe actual road surface when proper construction procedure isused in the placement of the material. The specimens may beused to determine stability, density, strength, water suscepti-bility, etc., of bituminous mixtures by specified test methods.5. Apparatus5.1 Gyratory-Shear Molding Press:
7、5.1.1 Press Platen, which is hardened and ground flat.5.1.2 Hydraulic Compaction Ram, with nonrotating metalface as shown in Fig. 1 and Fig. 2. The ram face is hardenedand ground flat. The ram varies the vertical opening betweenthe ram face and the press platen from + 11 cm (4.5 in.) downto less tha
8、n 2.5 cm (1.0 in.).5.1.3 Low-Pressure Gage, with automatic valve for highpressure protection and with a capability of indicating within62 kPa (60.3 psi) the following: (See Note 1):5.1.3.1 Pregyration Stress219 kPa (31.8 psi), which is1779 N (400 lbf) total for 10-cm or 4-in. diameter specimens.5.1.
9、3.2 End Point Stress 657 kPa (95.3 psi), which is5338 N (1200 lbf) total for 10-cm or 4-in. diameter specimens.5.1.4 High-Pressure Gage, with capability of indicatingwithin 6110 kPa (616 psi) the following: (See Note 1):5.1.4.1 Consolidation Stress11.0 MPa (1590 psi), whichis 89 kN (20 000 lbf) tota
10、l for 10-cm or 4-in. diameterspecimens.5.1.5 Tilt Mechanism, to cock the mold 6 while thespecimen is under pregyration stress (see 5.1.3.1). In reversemanner, it squares the mold axially against the press platen,with a smooth quick motion.5.1.6 Gyration Mechanism, to move the mold about the ramface
11、12 total angle and produce gyratory shear compaction ofthe specimen.An electric motor drives the gyration mechanismat approximately 1 s/cycle.5.1.7 Count Mechanism, to shut the gyration motor off afterthree complete cycles and to stop it in the loading position withan electric brake.5.1.8 Hydraulic
12、Hand Pump, which meters 0.51-mm(0.020-in.) ram movement, with a smooth quick motion.5.2 Gyratory Mold Rigid metal mold as shown in Fig. 1and Fig. 3, with a concentric hardened ring for manipulatinggyratory action, and hardened to at least 55 HRC honed andhard-plated interior.5.3 Base PlateSolid meta
13、l plate as shown in Fig. 1 andFig. 2. Top and bottom surfaces are hardened and ground flat.( See Table 1 for a comparison of dimensions.)5.4 Wide-Mouth Funnel, with mouth that fits inside mold.5.5 Scale or Balance, having at least 4500-g capacity,sensitive to 0.1 g.5.6 Sieve or Screen A 25-mm (1-in.
14、) screen or 22.4-mm(78-in.) sieve.1This practice is under the jurisdiction of ASTM Committee D04 on Road andPaving Materials and is the direct responsibility of Subcommittee D04.20 onMechanical Tests of Bituminous Mixtures.Current edition approved Dec. 1, 2005. Published December 2005. Originallyapp
15、roved in 1981. Last previous edition approved in 1998 as D 4013 98.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM we
16、bsite.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.7 SpatulaA flexible spatula having a blade about 100mm (4 in.) long and 20 mm (34 in.) wide.5.8 SpoonA large spoon with a right angle bend betweenthe bowl and handle.5.9 Measuri
17、ng Device A micrometer dial assembly orcalipers for determining the height of the specimens is suitablefor this purpose.5.10 Specimen Extrusion DeviceA rigid right cylinder,having a minimum height of 115 mm (412 in.), and a diameterof approximately 98 mm (378 in.) to be used as a pedestal witha conv
18、erted arbor press or some similar device. Other methodsof specimen extrusion that do not damage the specimen may beused.5.11 Oven, for specimen mixtures and mold assemblieshaving a range from 38 to 150C (100 to 300F) and thermo-statically controlled to within 63C (65F).5.12 Miscellaneous Thermometer
19、s, trowels, gloves, andmixing pans.NOTE 1Because the effective diameter of the ram is different than theFIG. 1 Mold AssemblyFIG. 2 Ram Face and Base PlateFIG. 3 MoldD 4013 98 (2005)2nominal inside diameter of the mold, the hydraulic pressure on the ram isnot the same as the stress on the specimen. (
20、The hydraulic pressure on theram for many presses is equal to 50 psi, 150 psi and 2500 psi forPregyration Stress, End Point Stress, and Consolidation Stress, respec-tively.)6. Materials6.1 Kerosine.6.2 Lubricating Oil, lightweight grade.6.3 Paper Disks, 10-cm or 4-in. diameter.7. Test Specimen7.1 Pr
21、eparation of MixturePrepare the bituminous mix-ture in accordance with the specified test method.7.2 Amount of MixturePrepare constant-weighed amountsof bituminous mixture such that the compacted specimenheights are within the tolerances of the specified test method. Ifan initial specimen height is
22、not within tolerances, revise theconstant weight of subsequent specimens by multiplying theinitial constant weight by the optimum height and dividing bythe initial height as follows:Revised constant weight 5initial constant weight! 3 optimum height!initial height(1)7.2.1 ExampleThe specified height
23、is 2.00 6 0.25 in. Theweight of the initial specimen is selected to be 2500.0 g, and itis compacted to 2.32 in. The constant weight for the next andsubsequent specimens of this mixture should be (2500.0g 3 2.00 in.)/2.32 in.; or 2155.2 g.8. Calibration8.1 Gage Scales, The scales on the low- and high
24、-pressuregages may indicate the pressure of the hydraulic system or theforce of the ram. Distinct points on the low pressure gage mustbe determined for pregyration stress (5.1.3.1) and end pointstress (5.1.3.2), and one point on the high pressure gage for theconsolidation stress (5.1.4.1).38.2 Verif
25、ication The low- and high-pressure gages shouldbe verified on the gyratory-shear molding press at the pointsdetermined in 8.1, in accordance with Method E4.9. Preparation for Test and Compaction Temperatures9.1 Mix hot-mix asphaltic concrete mixtures that containasphalt cement and compact into test
26、specimens at a tempera-ture of 121 6 3C (250 6 5F).9.2 Place hot-mix, cold-laid mixtures and rock asphaltmixtures in an oven, cure to constant weight at a temperatureof 60 6 6C (140 6 10F) to remove moisture or hydrocarbonvolatiles, and mold at a temperature of 38 6 3C (100 6 5F).Curing to a “consta
27、nt weight” may be accomplished by dryingfor a specific period of time that has proven by experiment tobe adequate or drying to the point that by observation, based onexperience, the material is sufficiently dry for testing. Dryingshould be accompanied by frequent stirring.9.3 If the mixture (such as
28、 one obtained from an asphalticconcrete plant) contains aggregate larger than 22.4 mm (78 in.),separate the large size aggregate from the sample by means ofa 22.4-mm sieve (or a 25.0-mm (1-in.) round opening screen).Use the trowel to rub the material through the sieve, scrape off,and recover as much
29、 of the fines clinging to oversize particlesas possible.9.4 Preheat the mold and base plate in an oven to approxi-mately 60 to 93C (140 to 200F). For hot-mix, cold-laidmixtures and rock asphalt mixtures, heat to 38C (100F).Make certain that the gyratory mechanism is in proper workingorder and in the
30、 loading position. Connect the motorizedgyratory-shear molding press to its electrical outlet, and switchon the gyration mechanism, allowing the press to go throughone set of gyrations.9.5 Place a small amount of lightweight oil in the center ofthe motorized press platen and a drop or two on the sur
31、faces ofthe lower bearing. (This is the bearing that “cocks” the moldand gives or creates the gyratory action.) Squirt a small ring ofoil around the periphery of the top surface of the molds ring,in the path that the upper bearing will follow during thegyration. Do not use an excessive amount. When
32、molding anumber of specimens, this step should be repeated as appearsnecessary for adequate lubrication.9.6 Remove the mold and base plate from the oven and wipethe inside of the mold with a rag lightly moistened withkerosene or light lubricating oil. Insert the base plate into themold with the larg
33、e diameter up, and cover with a paper disk.Using the bent spoon and wide-mouthed funnel, transfer thelaboratory mixtures, or a weighed quantity of plantmixedmaterial, heated to proper molding temperature, in two ap-proximately equal layers, into the mold. Use the small spatulato move any large aggre
34、gate a small distance away from anysurface that must be molded smooth. Level the top of eachlayer while pressing the material downward with the spoon.Place a paper disk on top of the mixture. Be careful to avoidloss of material and segregation of particles.9.7 Slide the hot mold and contents to the
35、edge of the worktable, and with a gloved hand holding the base plate in place,transport the mold to the platen of the press. Slide the moldonto the platen and center it in the molding position beneath theram of the press. Pump the ram down into the center of the3Original presses had 3.19-in. diamete
36、r jack cylinders such that the three stresspoints on the gage were 50, 150, and 2500-psi (345, 1034, and 17 237-kPa)hydraulic pressures, respectively.TABLE 1 Dimensions of Fig. 2 and Fig. 3Preferred AlternativeDimension mm Tolerance mm ToleranceA 100.00 +0.00 101.60 +0.000.05 0.05B 2.54 +0.00 2.54 +
37、0.000.25 0.25C 1.57 60.25 1.57 60.25D 25.40 60.38 25.40 60.38E 14.27 60.38 14.27 60.38F 100.25 60.05 101.85 60.05G 100.00 +0.00 101.60 +0.000.13 0.13H 1.57 60.13 1.57 60.13I 3.18 60.25 3.18 60.25D 4013 98 (2005)3mold. Continue pumping until the low pressure gage reachesthe pregyration stress point (
38、5.1.3.1).10. Gyratory-Shear Compaction10.1 Immediately tilt the mold to the specified angle ofgyration. Be certain that the mold is tilted all the way. Themetering pump should be completely full, accomplished bylifting its handle all the way up.10.2 Switch on the gyrating mechanism. The mold isautom
39、atically gyrated three times and stopped.NOTE 2Experience has revealed that the smoothest operating proce-dure, and certainly the safest, is for the operator to keep one hand on thepump handle at all times while operating the controls with the other hand.11. End Point Trial11.1 As soon as the mold s
40、tops gyrating, reverse the tiltmechanism to square the mold, and immediately follow withone full stroke of the metering pump. Squaring the mold andthe test pump stroke must be two smooth, complete, andconsecutive motions. (The speed of the full stroke of the pumpis important because this serves as t
41、he end point criteria for theprocedure. The proper pumping speed is one full stroke inapproximately one second.) Observe the low-pressure gageduring the one full stroke of the metering pump; this isimportant because it checks for the end point of gyratory-shearcompaction.11.2 If the low-pressure gag
42、e does not reach end point stress(5.1.3.2), adjust the pressure to pregyration stress (5.1.3.1), andrepeat the procedure in Section 10. During molding when thegage comes to rest between pregyration stress and end pointstress, drop the pressure below pregyration stress and pumpback up to it:11.2.1 Ex
43、ampleSuppose the pregyration stress is 345 kPa(50 psi) on the low-pressure gage and the end point stress is1034 kPa (150 psi). If the mold is squared and the test pumpstroked once, three types of conditions are possible:11.2.1.1 The low-pressure gage goes to 414 kPa (60 psi) anddrops to 310 kPa (45
44、psi); pump to 345 kPa and repeat theprocedure in Section 10.11.2.1.2 The low-pressure gage reaches 965 kPa (140 psi)and drops to 793 kPa (115 psi); release the pressure toapproximately 276 kPa (40 psi), pump to 345 kPa (50 psi), andrepeat the procedure in Section 10.11.2.1.3 The low-pressure gage re
45、aches 1048 kPa (152 psi)and drops, which indicates that compaction is completed inaccordance with 12.1; proceed as described in 12.2 through12.6.12. Completion of Test12.1 The gyratory-shear compaction and the end point trialare repeated alternately until one nonviolent stroke of themetering pump ca
46、uses the gage to surge to end point stress(5.1.3.2) or higher, thus indicating completion of the gyratory-shear portion.12.2 Pump slowly until the automatic gage protector valvecuts the low-pressure gage out of the system. Then, atapproximately one stroke per second, pump the pressure up toconsolida
47、tion stress (5.1.4.1), as measured by the high-pressuregage.12.3 As soon as the gage registers consolidation stress, stoppumping with the one hand, and with the other very carefullybleed-off the pressure, watching the descent of the high-pressure gage when releasing stress so as to prevent damage to
48、the gage.12.4 Pump the ram up and out of the mold. Slide the moldout of the press, remembering to place a gloved hand beneaththe mold to keep the base plate from falling out. Remove thespecimen from the mold by placing the assembly on theextrusion pedestal and, with the aid of a converted arbor pres
49、sor some similar device, force the mold off the specimen. (Othermethods of specimen extrusion that do not damage the speci-men may be used.)12.5 Measure the height of the specimen for conformity tothe specified test method (see 7.2), and log it in if satisfactory.12.6 Clean the mold on the inside with a kerosine rag beforemolding another specimen.NOTE 3It should be emphasized that this motorized press must bekept clean. If dirt and grit collect on the platen, ram face, or hardened steelring, wipe it off and re-oil before molding
