1、Designation: D 6270 08Standard Practice forUse of Scrap Tires in Civil Engineering Applications1This standard is issued under the fixed designation D 6270; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、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, andleachate genera
3、tion 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 included in thisstan
4、dard.2. Referenced Documents2.1 ASTM Standards:2C 127 Test Method for Density, Relative Density (SpecificGravity), and Absorption of Coarse AggregateC 136 Test Method for Sieve Analysis of Fine and CoarseAggregatesD 698 Test Methods for Laboratory Compaction Character-istics of Soil Using Standard E
5、ffort (12 400 ft-lbf/ft3(600kN-m/m3)D 1557 Test Methods for Laboratory Compaction Charac-teristics of Soil Using Modified Effort (56,000 ft-lbf/ft3(2,700 kN-m/m3)D 2434 Test Method for Permeability of Granular Soils(Constant Head)D 3080 Test Method for Direct Shear Test of Soils UnderConsolidated Dr
6、ained ConditionsD 4253 Test Methods for Maximum Index Density and UnitWeight of Soils Using a Vibratory Table2.2 American Association of State Highway and Transpor-tation Offcials Standard:T 274 Standard Method of Test for Resilient Modulus ofSubgrade Soils32.3 U.S. Environmental Protection Agency S
7、tandard:Method 1311 Toxicity Characteristics Leaching Procedure43. Terminology3.1 Definitions:3.1.1 baling, na method of volume reduction wherebytires are compressed 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 thepli
8、es.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 brass plated high tensile steel wire cordused in steel belts.3.1.5 buffng rubber, nvulcanized rubber usually obtainedfrom a worn or used tire
9、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. 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 dimen
10、sions.3.1.10 granulated rubber, nparticulate rubber composedof mainly non-spherical particles that span a broad range ofmaximum particle dimension, from below 425 m (40 mesh) to12 mm (also refer to particulate rubber).53.1.11 ground rubber, nparticulate rubber composed ofmainly non-spherical particl
11、es that span a range of maximumparticle dimensions, from below 425 m (40 mesh) to 2 mm(also refer to particulate rubber).53.1.12 nominal size, nthe average size product that com-prises 50 % or more of the throughput in a scrap tire processingoperation; scrap tire processing operations generate produ
12、ctsabove and below the nominal size.3.1.13 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 prevent1This practice is under the
13、 jurisdiction of ASTM Committee D34 on WasteManagement and is the direct responsibility of Subcommittee D34.03.03 onIndustrial Recovery and Reuse.Current edition approved Sept. 1, 2008. Published December 2008. Originallyapproved in 1998. Last previous edition approved in 2004 as D 6270 98 (2004).2F
14、or 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 Metho
15、ds of Samplingand Testing, Part II: Methods of Sampling and Testing, American Association ofState Highway and Transportation Officials, Washington, DC.4Test Methods for Evaluating Solid Waste: Physical/Chemical Methods, 3rded.,Report No. EPA 530/SW-846, U.S. Environmental Protection Agency, Washingt
16、on,DC.5The defined term is the responsibility of Committee D11 on Rubber.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.agglomeration during production, transportation, or storage(also see definition of buffng rubber, granulated rub
17、ber,ground rubber, and powdered rubber).53.1.14 passenger car tire, na tire with less than a 457-mmrim diameter for use on cars only.3.1.15 powdered rubber, nparticulate rubber composed ofmainly non-spherical particles that have a maximum particledimension equal to or below 425 m (40 mesh) (also ref
18、er toparticulate rubber).53.1.16 preliminary remediation guideline, nrisk-basedconcentrations that the USEPA considers to be protective forlifetime exposure to humans.3.1.17 rough shred, na piece of a shredded tire that islarger than 50 mm by 50 mm by 50 mm, but smaller than 762mm by 50 mm by 100 mm
19、.3.1.18 rubber fines, nsmall particles of ground rubber thatresult as a by-product of producing shredded rubber.3.1.19 scrap tire, na tire which can no longer be used forits original purpose due to wear or damage.3.1.20 shred sizing, na term which generally refers to theprocess of particles passing
20、through a rated screen openingrather than those which are retained on the screen.3.1.21 shredded tire, na size reduced scrap tire where thereduction in size was accomplished by a mechanical processingdevice, commonly referred to as a shredder.3.1.22 shredded rubber, npieces of scrap tires resultingf
21、rom mechanical processing.3.1.23 sidewall, nthe side of a tire between the treadshoulder and the rim bead.3.1.24 single pass shred, na shredded tire that has beenprocessed by one pass through a shear type shredder and theresulting pieces have not been classified by size.3.1.25 steel belt, nrubber co
22、ated steel cords that rundiagonally under the tread of steel radial tires and extend acrossthe tire approximately the width of the tread.3.1.26 tire chips, npieces of scrap tires that have a basicgeometrical shape and are generally between 12 and 50 mm insize and have most of the wire removed (Syn.
23、chipped tire).3.1.27 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 applications. Also see definition of tire chips andtire shreds.3.1.28 tire shreds, npieces of scrap
24、 tires that have a basicgeometrical shape and are generally between 50 and 305 mmin size.3.1.29 tread, nthat portion of the tire which contacts theroad.3.1.30 truck tire, na tire with a rim diameter of 500 mmor larger.3.1.31 waste tire, na tire which is no longer capable ofbeing used for its origina
25、l purpose but which has been disposedof in such a manner that it can not be used for any otherpurpose.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
26、 passes througha standard sieve with an x-mm opening size (that is, 25-mmminus; 50-mm minus; 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
27、 whole scrap tiresin civil engineering applications. This includes use of TDAandTDA/soil mixtures as lightweight embankment fill, lightweightretaining wall backfill, drainage layers for roads, landfills andother applications, thermal insulation to limit frost penetrationbeneath roads, insulating bac
28、kfill to limit heat loss frombuildings, vibration damping layers for rail lines, and replace-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 wel
29、l as use as fill when whole tires have beencompressed into bales. It is the responsibility 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. T
30、his practice is intended to encourage wider utili-zation of scrap tires in civil engineering 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
31、 of a deleterious heating reaction (1).6Guidelines have been developed to minimize internal 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 Characterization
32、5.1 The specific gravity and water absorption capacity ofTDA should be determined in accordance with Test MethodC 127. 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
33、of the specified value. The particle density or density ofsolids of TDA (rs) may be determined from the apparentspecific gravity using the following equation:rs5 Sarw! (1)where:Sa= apparent specific gravity, andrw= density of water.5.2 The gradation of TDA should be determined in accor-dance with Te
34、st Method C 136. However, the specific gravityof TDA is less than half the values obtained for commonearthen materials, so it is permissible to use a minimum weightof test sample that is half of the specified value.5.3 The laboratory compacted dry density (or bulk density)of TDAand TDA/soil mixtures
35、 with less than 30 % retained on6The boldface numbers in parentheses refer to the list of references at the end ofthis standard.D6270082the 19.0-mm sieve can be determined in accordance with TestMethod D 698 or D 1557. However, TDA and TDA/soilmixtures used for civil engineering applications almost
36、alwayshave more 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,o
37、r the number of blows of the rammer per layer, or both, beincreased to produce the desired compactive energy per unitvolume. Compactive energies ranging from 60 % of TestMethod D 698 (60 % 3 600 kN-m/m3= 360 kN-m/m3)to100 % of Test Method D 1557 (2700 kN-m/m3) have beenused. Compaction energy has on
38、ly a small effect on theresulting dry density (3); thus, for most applications it ispermissible to use a compactive energy equivalent to 60 % ofTest Method D 698. To achieve this energy with a mold volumeof 0.0125 m3would require that the sample be compacted in 5layers with 44 blows per layer with a
39、 44.5 N rammer falling457 mm. The water content of the sample has only a smalleffect on the compacted dry density (3) so it is permissible toperform compaction tests on air or oven-dried samples.5.3.1 The dry densities for TDA loosely dumped into acompaction mold and TDA compacted by vibratory metho
40、ds(similar to Test Method D 4253) are about the same (4, 5, 6).Thus, vibratory compaction of TDA in the laboratory (see TestMethod D 4253) 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 an
41、y overlying material 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 m
42、easured by placing TDA 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-m
43、ented to measure the 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
44、 a significant portion 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 TDAFIG. 1 Compressibility Apparatus for TDA Designed to Measured Lateral Stress an
45、d the Portion of the Vertical Load Transferred byFriction from TDA to Container (10)TABLE 1 Size of Compaction Molds Used to Determine DryDensity of TDAMaximum Particle Size(mm)Mold Diameter(mm)Mold Volume(m3)Reference75 254 0.0125 (3)75 305 0.0146 (4)51 203 and 305 N.R.A(5)AN.R. = not reported.D627
46、0083will be underestimated. For all compressibility tests, the insideof the container should be lubricated 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 str
47、ess at the top and thebottom of the sample should be measured so that the averagevertical stress in the 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:u = first invaria
48、nt of stress (sum of the three principalstresses),A = experimentally determined parameter, andB = experimentally 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 whic
49、hprecludes the general applicability of this procedure to thelarger size TDA typically used for civil engineering 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:sh= measured horizontal stress, andsv= measured vertical stress.5.7 The shear strength of TDA may be determined
