1、Designation: D6270 08 (Reapproved 2012)Standard Practice forUse of Scrap Tires in Civil Engineering Applications1This standard is issued under the fixed designation D6270; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、 last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice provides guidance for testing the physicalproperties, design considerations, construction practices, an
3、dleachate generation potential of processed or whole scrap tiresin lieu of conventional civil engineering materials, such asstone, gravel, soil, sand, lightweight aggregate, or other fillmaterials.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are incl
4、uded in thisstandard.2. Referenced Documents2.1 ASTM Standards:2C127 Test Method for Density, Relative Density (SpecificGravity), and Absorption of Coarse AggregateC136 Test Method for Sieve Analysis of Fine and CoarseAggregatesD698 Test Methods for Laboratory Compaction Character-istics of Soil Usi
5、ng Standard Effort (12 400 ft-lbf/ft3(600kN-m/m3)D1557 Test Methods for Laboratory Compaction Charac-teristics of Soil Using Modified Effort (56,000 ft-lbf/ft3(2,700 kN-m/m3)D2434 Test Method for Permeability of Granular Soils(Constant Head)D3080 Test Method for Direct Shear Test of Soils UnderConso
6、lidated Drained ConditionsD4253 Test Methods for Maximum Index Density and UnitWeight of Soils Using a Vibratory TableD2974 Test Methods for Moisture,Ash, and Organic Matterof Peat and Other Organic Soils2.2 American Association of State Highway and Transpor-tation Offcials Standard:T 274 Standard M
7、ethod of Test for Resilient Modulus ofSubgrade Soils3M 288 Standard Specification for Geotextiles42.3 U.S. Environmental Protection Agency Standard:Method 1311 Toxicity Characteristics Leaching Procedure53. Terminology3.1 Definitions:3.1.1 baling, na method of volume reduction wherebytires are compr
8、essed into bales.3.1.2 bead, nthe anchoring part of the tire which is shapedto fit the rim and is constructed of bead wire wrapped by theplies.3.1.3 bead wire, na high tensile steel wire surrounded byrubber, which forms the bead of a tire that provides a firmcontact to the rim.3.1.4 belt wire, na br
9、ass plated high tensile steel wire cordused in steel belts.3.1.5 buffng rubber, nvulcanized rubber usually obtainedfrom a worn or used tire in the process of removing the oldtread in preparation for retreading.3.1.6 carcass, nsee casing.3.1.7 casing, nthe basic tire structure excluding the tread(Syn
10、 carcass).3.1.8 chipped tire, nsee tire chip.3.1.9 chopped tire, na scrap tire that is cut into relativelylarge pieces of unspecified dimensions.3.1.10 granulated rubber, nparticulate rubber composedof mainly non-spherical particles that span a broad range of1This practice is under the jurisdiction
11、 of ASTM Committee D34 on WasteManagement and is the direct responsibility of Subcommittee D34.03 on Treatment,Recovery and Reuse.Current edition approved Sept. 1, 2012. Published December 2012. Originallyapproved in 1998. Last previous edition approved in 2008 as D6270 08. DOI:10.1520/D6270-08R12.2
12、For 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 website.3Standard Specifications for Transportation Materials and Meth
13、ods of Samplingand Testing, Part II: Methods of Sampling and Testing, American Association ofState Highway and Transportation Officials, Washington, DC.4Standard Specifications for Transportation Materials and Methods of Samplingand Testing, Part I: Specifications, American Association of State High
14、way andTransportation Officials, Washington, DC.5Test Methods for Evaluating Solid Waste: Physical/Chemical Methods, 3rded.,Report No. EPA 530/SW-846, U.S. Environmental Protection Agency, Washington,DC.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-29
15、59, United States.maximum particle dimension, from below 425 m (40 mesh) to12 mm (also refer to particulate rubber).63.1.11 ground rubber, nparticulate rubber composed ofmainly non-spherical particles that span a range of maximumparticle dimensions, from below 425 m (40 mesh) to 2 mm(also refer to p
16、articulate rubber).63.1.12 mineral soil, nsoil containing less than5%or-ganic matter as determined by a loss on ignition test (D2974).3.1.13 nominal size, nthe average size product that com-prises 50 % or more of the throughput in a scrap tire processingoperation; scrap tire processing operations ge
17、nerate productsabove and below the nominal size.3.1.14 particulate rubber, nraw, uncured, compounded orvulcanized rubber that has been transformed by means of amechanical size reduction process into a collection of particles,with or without a coating of a partitioning agent to preventagglomeration d
18、uring production, transportation, or storage(also see definition of buffng rubber, granulated rubber,ground rubber, and powdered rubber).63.1.15 passenger car tire, na tire with less than a 457-mmrim diameter for use on cars only.3.1.16 powdered rubber, nparticulate rubber composed ofmainly non-sphe
19、rical particles that have a maximum particledimension equal to or below 425 m (40 mesh) (also refer toparticulate rubber).63.1.17 preliminary remediation guideline, nrisk-basedconcentrations that the USEPA considers to be protective forlifetime exposure to humans.3.1.18 rough shred, na piece of a sh
20、redded tire that islarger than 50 mm by 50 mm by 50 mm, but smaller than 762mm by 50 mm by 100 mm.3.1.19 rubber fines, nsmall particles of ground rubber thatresult as a by-product of producing shredded rubber.3.1.20 scrap tire, na tire which can no longer be used forits original purpose due to wear
21、or damage.3.1.21 shred sizing, na term which generally refers to theprocess of particles passing through a rated screen openingrather than those which are retained on the screen.3.1.22 shredded tire, na size reduced scrap tire where thereduction in size was accomplished by a mechanical processingdev
22、ice, commonly referred to as a shredder.3.1.23 shredded rubber, npieces of scrap tires resultingfrom mechanical processing.3.1.24 sidewall, nthe side of a tire between the treadshoulder and the rim bead.3.1.25 single pass shred, na shredded tire that has beenprocessed by one pass through a shear typ
23、e shredder and theresulting pieces have not been classified by size.3.1.26 steel belt, nrubber coated steel cords that rundiagonally under the tread of steel radial tires and extend acrossthe tire approximately the width of the tread.3.1.27 tire chips, npieces of scrap tires that have a basicgeometr
24、ical shape and are generally between 12 and 50 mm insize and have most of the wire removed (Syn. chipped tire).3.1.28 tire derived aggregate (TDA), npieces of scraptires that have a basic geometrical shape and are generallybetween 12 and 305 mm in size and are intended for use in civilengineering ap
25、plications. Also see definition of tire chips andtire shreds.3.1.29 tire shreds, npieces of scrap tires that have a basicgeometrical shape and are generally between 50 and 305 mmin size.3.1.30 tread, nthat portion of the tire which contacts theroad.3.1.31 truck tire, na tire with a rim diameter of 5
26、00 mmor larger.3.1.32 whole tire, na scrap tire that has been removedfrom a rim, but which has not been processed.3.1.33 x-mm minus, npieces of classified, size-reducedscrap tires where a minimum of 95 % by weight passes througha standard sieve with an x-mm opening size (that is, 25-mmminus; 50-mm m
27、inus; 75-mm minus, etc.).4. Significance and Use4.1 This practice is intended for use of scrap tires including:tire derived aggregate (TDA) comprised of pieces of scraptires, TDA/soil mixtures, tire sidewalls, and whole scrap tiresin civil engineering applications. This includes use of TDAandTDA/soi
28、l mixtures as lightweight embankment fill, lightweightretaining wall backfill, drainage layers for roads, landfills andother applications, thermal insulation to limit frost penetrationbeneath roads, insulating backfill to limit heat loss frombuildings, vibration damping layers for rail lines, and re
29、place-ment for soil or rock in other fill applications. Use of wholescrap tires and tire sidewalls includes construction of retainingwalls, drainage culverts, road-base reinforcement, and erosionprotection, as well as use as fill when whole tires have beencompressed into bales. It is the responsibil
30、ity of the designengineer to determine the appropriateness of using scrap tiresin a particular application and to select applicable tests andspecifications to facilitate construction and environmentalprotection. This practice is intended to encourage wider utili-zation of scrap tires in civil engine
31、ering applications.4.2 Three TDA fills with thicknesses in excess of 7 m haveexperienced a serious heating reaction. However, more than100 fills with a thickness less than 3 m have been constructedwith no evidence of a deleterious heating reaction (1).7Guidelines have been developed to minimize inte
32、rnal heatingof TDA fills (2) as discussed in 6.11. The guidelines areapplicable to fills less than 3 m thick. Thus, this practice shouldbe applied only to TDA fills less than 3 m thick.5. Material Characterization5.1 The specific gravity and water absorption capacity ofTDA should be determined in ac
33、cordance with Test MethodC127. However, the specific gravity of TDA is less than halfthe value obtained for common earthen coarse aggregate, so itis permissible to use a minimum weight of test sample that ishalf of the specified value. The particle density or density ofsolids of TDA (s) may be deter
34、mined from the apparentspecific gravity using the following equation:6The defined term is the responsibility of Committee D11 on Rubber.7The boldface numbers in parentheses refer to the list of references at the end ofthis standard.D6270 08 (2012)2rs5 Sarw! (1)where:Sa= apparent specific gravity, an
35、dw= density of water.5.2 The gradation of TDA should be determined in accor-dance with Test Method C136. However, the specific gravity ofTDA is less than half the values obtained for common earthenmaterials, so it is permissible to use a minimum weight of testsample that is half of the specified val
36、ue.5.3 The laboratory compacted dry density (or bulk density)of TDAand TDA/soil mixtures with less than 30 % retained onthe 19.0-mm sieve can be determined in accordance with TestMethod D698 or D1557. However, TDA and TDA/soil mix-tures used for civil engineering applications almost alwayshave more
37、than 30 % retained on the 19.0-mm sieve, so thesemethods generally are not applicable. A larger compactionmold should be used to accommodate the larger size of theTDA. The sizes of typical compaction molds are summarizedin Table 1. The larger mold requires that the number of layers,or the number of
38、blows of the rammer per layer, or both, beincreased to produce the desired compactive energy per unitvolume. Compactive energies ranging from 60 % of TestMethod D698 (60 % 3 600 kN-m/m3= 360 kN-m/m3)to100 % of Test Method D1557 (2700 kN-m/m3) have been used.Compaction energy has only a small effect
39、on the resulting drydensity (3); thus, for most applications it is permissible to usea compactive energy equivalent to 60 % of Test Method D698.To achieve this energy with a mold volume of 0.0125 m3wouldrequire that the sample be compacted in 5 layers with 44 blowsper layer with a 44.5 N rammer fall
40、ing 457 mm. The watercontent of the sample has only a small effect on the compacteddry density (3) so it is permissible to perform compaction testson air or oven-dried samples.5.3.1 The dry densities for TDA loosely dumped into acompaction mold and TDA compacted by vibratory methods(similar to Test
41、Method D4253) are about the same (4, 5, 6).Thus, vibratory compaction of TDA in the laboratory (see TestMethod D4253) should not be used.5.3.2 When estimating an in-place density for use in design,the compression of a TDA layer under its own self-weight andunder the weight of any overlying material
42、must be considered.The dry density determined as discussed in 5.3 are uncom-pressed values. In addition, short-term time dependent settle-ment of TDAshould be accounted for when estimating the finalin-place density (7).5.4 The compressibility of TDA and TDA/soil mixtures canbe measured by placing TD
43、A in a rigid cylinder with adiameter several times greater than the largest particle size andthen measuring the vertical strain caused by an increasingvertical stress. If it is desired to calculate the coefficient oflateral earth pressure at rest KO, the cylinder can be instru-mented to measure the
44、horizontal stress of the TDA acting onthe wall of the cylinder.5.4.1 The high compressibility of TDA necessitates the useof a relatively thick sample. In general, the ratio of the initialspecimen thickness to sample diameter should be greater thanone. This leads to concerns that a significant portio
45、n of theapplied vertical stress could be transferred to the walls of thecylinder by friction. If the stress transferred to the walls of thecylinder is not accounted for, the compressibility of the TDAwill be underestimated. For all compressibility tests, the insideof the container should be lubricat
46、ed to reduce the portion ofthe applied load that is transmitted by side friction from thesample to the walls of the cylinder. For testing where a highlevel of accuracy is desired, the vertical stress at the top and thebottom of the sample should be measured so that the averagevertical stress in the
47、sample can be computed. A test apparatusdesigned for this purpose is illustrated in Fig. 1 (8).5.5 The resilient modulus (MR) of subgrade soils can beexpressed as:MR5 AuB(2)where: = first invariant of stress (sum of the three principalstresses),A = experimentally determined parameter, andB = experim
48、entally determined parameter.5.5.1 Tests for the parameters A and B can be conductedaccording to AASHTO T 274. The maximum particle sizetypically is limited to 19 mm by the testing apparatus whichprecludes the general applicability of this procedure to thelarger size TDA typically used for civil eng
49、ineering applica-tions.5.6 The coefficient of lateral earth pressure at rest KOandPoissons ratio can be determined from the results ofconfined compression tests where the horizontal stresses weremeasured. A test apparatus designed for this purpose is shownin Fig. 1. KOand are calculated from:KO5shsv(3) 5KO1 1 KO!(4)where:h= measured horizontal stress, andv= measured vertical stress.5.7 The shear strength of TDA may be determined in adirect shear apparatus in accordance with Test Method D3080or using a triaxial shear apparatus. Th
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