1、Designation: D6454/D6454M 99 (Reapproved 2016)1Standard Test Method forDetermining the Short-Term Compression Behavior of TurfReinforcement Mats (TRMs)1This standard is issued under the fixed designation D6454/D6454M; the number immediately following the designation indicates theyear of original ado
2、ption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTEDesignation was changed to dual and units statement in 1.3 and units throughou
3、t were corrected editorially inJanuary 2016.1. Scope1.1 The test method establishes the procedures for evalua-tion of the deformations of a turf reinforcement mat (TRM)under short-term compressive loading. This test method isstrictly an index test method to be used to verify the compres-sive strengt
4、h consistency of a given manufactured geosyn-thetic. Results from this test method should not be consideredas an indication of actual or long-term performance of theTRM in field applications.1.2 Since these TRMs experience multidirectional compres-sive loadings in the field, this test method will no
5、t show actualfield performance and should not be used for this specificobjective. The evaluation of the results also should recognizethat the determination of the short term single plane compres-sive behavior of geosynthetics does not reflect the installedperformance of TRMs and, therefore, should n
6、ot be used as theonly method of product or performance specification.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Co
7、mbiningvalues from the two systems may result in non-conformancewith the standard.1.4 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 appro-priate safety and health practices and d
8、etermine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D4354 Practice for Sampling of Geosynthetics and RolledErosion Control Products(RECPs) for TestingD4439 Terminology for GeosyntheticsD5199 Test Method for Measuring the Nominal Thicknessof G
9、eosynthetics3. Terminology3.1 Definitions:3.1.1 compressive deformation, L, nthe decrease in gagelength produced in the test specimen by a compressive load.3.1.2 compressive strain, nd, nthe ratio of compressivedeformation to the gage length of the test specimen.3.1.3 gage length, L, nin compression
10、 testing, the mea-sured thickness of the test specimen under specified compres-sional force, expressed in units of length prior to compressiveloading. D51993.1.4 geosynthetic, na planar product manufactured frompolymeric material used with foundation, soil, rock, earth, orany other geotechnical engi
11、neering related material as anintegral part of a man-made project, structure, or system.D44393.1.5 index test, na test procedure which may contain aknown bias but which may be used to establish an order for aset of specimens with respect to the property of interest. D44393.1.6 yield point, nthe firs
12、t point on the load-deformationcurve at which an increase in deformation occurs without acorresponding increase in load.1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.05 on Geosyn-thetic Erosion Control.Current e
13、dition approved Jan. 1, 2016. Published January 2016. Originallyapproved in 1999. Last previous edition approved in 2011 as D645499(2011). DOI:10.1520/D6454_D6454M-99R16E01.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For A
14、nnual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.6.1 DiscussionSome geosynthetics do not exhibit anexact yield point. T
15、he tested TRM may exhibit a less steepslope at yield. In addition, it should be stated that the yieldpoint also may be the ultimate strength of the TRM.3.1.7 For definitions of terms relating to geotextiles, refer toTerminology D4439.4. Summary of Test Method4.1 Specimens are mounted between paralle
16、l plates in a loadframe. Compressive loads are applied at a constant rate ofcrosshead movement. The deformations are recorded as afunction of load. The compressive stress and strain are evalu-ated and plotted. The compressive yield point is evaluated fromthe stress/strain relationship for those mate
17、rials that exhibit adetectable compressive yield point.5. Significance and Use5.1 The compression behavior test for TRMs is intended tobe an index test. It is anticipated that the results of thecompression behavior test will be used to evaluate product.The results of the analyses also may be used to
18、 compare therelative compressive yield points of materials that exhibit adetectable compressive yield point. It is anticipated that thistest will be used for quality control testing to evaluateuniformity and consistency within a lot or between lots wheresample geometry factors, for example, thicknes
19、s, or materialsmay have changed.NOTE 1This is a one-dimensional test for compressive loading of aTRM in one plane.5.1.1 The compressive yield point of TRMs may be evalu-ated from the stress/strain relationship. Many materials exhibitcompressive deformation but may not show a distinct com-pressive yi
20、eld point.5.2 This test method can be used to evaluate the short-termstress/strain behavior of TRMs under compressive stress whileloaded at a constant rate of deformation.5.3 This test method may be used for acceptance testing ofcommercial shipments of TRMs but caution is advised becauseinterlaborat
21、ory testing is incomplete.5.3.1 In the case of a dispute arising from differences inreported test results when using this test method for acceptancetesting of commercial shipments, the purchaser and the sup-plier should conduct comparative tests to determine if there isstatistically bias between the
22、ir laboratories. Competent statis-tical assistance is recommended for the investigations of bias.As a minimum, two parties should take a group of testspecimens from material shipped to project. The test specimensthen should be assigned randomly in equal numbers to eachlaboratory for testing. The ave
23、rage results from the twolaboratories should be compared using the Students t-test forunpaired data and an acceptable probability level chosen by thetwo parties before the testing is begun. If bias is found, eitherits cause must be found and corrected, or the purchaser andsupplier must agree to inte
24、rpret future test results in the light ofthe known bias.6. Apparatus6.1 Loading MechanismThe loading mechanism shall becapable of applying compressive loads at a constant rate ofdeformation of 10 % on the nominal thickness of the testspecimen/min or 1 mm/min, whichever is greater.NOTE 2Some loading
25、mechanisms, especially the older models, donot have the capability of adjusting the rate of deformation to the specificrate required. For these instruments, the user and producer shouldestablish mutually agreed upon testing rates; however, the rate ofdeformation selected should not be greater than 1
26、0 % on the nominalthickness of the test specimen/min or 1 mm/min, whichever is greater.6.2 Fixed PlateThe bottom fixed plate shall be larger thanthe specimen to be tested. It shall be flat, smooth, andsupported completely and uniformly.NOTE 3It is recommended that the minimum fixed plate width beequ
27、al to the sample width plus twice the thickness of the test sample. Thisshould support the sample through the range of deformation and preventdraping or flexing displacement.6.3 Movable PlateThe movable plate shall be of sufficientthickness and strength to preclude any bending during loading.It shal
28、l be parallel to the bottom fixed plate and attached to thecompression mechanism. A spherical loading block of thesuspended, self-aligning type is recommended. The dimensionsand shape of the top movable, plate shall depend on thespecimen dimensions and geometry. In general, both lengthand width of t
29、he top movable plate should each be at least 20 %greater than the length and width of the specimens.6.4 Load IndicatorUse a load-indicating mechanism thathas an accuracy of 61 % of the maximum indicated value ofthe test (force).6.5 Deformation IndicatorUse a deformation-indicatingmechanism that has
30、an accuracy of 61.0 % of the maximumindicated value of the test (deformation).6.6 Micrometer Dial Gage, caliper or steel rule, suitable formeasuring dimensions of the specimens to +1 %.7. Sampling7.1 Lot SampleDivide the product into lots and take thelot sample as directed in Practice D4354.7.2 Labo
31、ratory SampleUnits in the laboratory sampleshould be the same as the units in the lot sample for the lot tobe tested. Take a sample extending across the full width, that is,cross-machine direction, of the TRM production unit of suffi-cient length, that is, machine direction, so that the requirements
32、of 7.3 can be met. Take a sample that will exclude materialfrom the outer wrap of a roll, if applicable, unless the sampleis taken at the production site, then the inner and outer wrapmaterial may be used.7.3 Test SpecimensCut five specimens from each unit inthe laboratory sample with each specimen
33、being at least 120 by120 mm/mm24.7 by 4.7 in.2.8. Conditioning8.1 Bring the specimens to the moisture and temperatureequilibrium in the atmosphere for testing permanent rollederosion control products, that is, a temperature of 21 + 2C70 + 4F and a relative humidity of 60 + 10 %.D6454/D6454M 99 (2016
34、)129. Procedure9.1 Measure the length, width and thickness of the specimento an accuracy of 61%.9.1.1 The nominal thickness shall be determined using TestMethod D5199.9.2 The test specimen shall be placed on the bottom plateand centered with respect to the axis of the loading mechanism.The loading m
35、echanism shall be moving at the requiredconstant speed at or before the point of contact with thesample.9.3 The rate of crosshead movement shall be 10 % on thenominal thickness of the test specimen/min or 1 6 0.1 mm0.04 6 0.004 in./min, whichever is greater or as agreed uponbetween the user and manu
36、facturer.9.4 Use crosshead movement as a measure of deformation.If an automatic recorder is not used, measure the deformationin increments no greater than 0.5 % of the original thickness ofthe specimen. At each measurement, record the deformationand the corresponding load.9.5 Continue until a yield
37、point is reached, or until themaximum acceptable deformation limit has been reached,whichever occurs first.9.6 The test specimen then should be unloaded and removedfrom the loading mechanism.FIG. 1 Typical Load Deformation CurveFIG. 2 Stress Strain CurveD6454/D6454M 99 (2016)139.7 Repeat the precedi
38、ng procedures until five specimensare tested.10. Calculation10.1 If an automatic recorder is not used, construct aload-deformation curve from the incremental values obtainedin accordance with 9.4.10.2 In a typical load-deformation curve (see Fig. 1) there isa toe region, AC, that may not represent a
39、 property of thematerial. It is an artifact caused by the alignment or seating ofthe specimen. If such a circumstance arises, in order to obtaincorrect values of such parameters as strain, yield point, etc.,this artifact must be compensated for to give the corrected zeropoint on the deformation axis
40、. Using a straightedge, carefullyextend to the zero force line the steepest portion of theforce-deflection or force-strain curve. This establishes the“zero deformation” or “zero strain” points (Point B in Fig. 1).Measure all distances for deformation or strain calculationsfrom this point.10.2.1 If t
41、here is a compressive yield point (as Point Y inFig. 1), read the load and measure the specimen deformation(distance B-D). Calculate the residual thickness of the speci-mens at various fixed loads in addition to the yield point.Follow this with a report that indicates the values of both yieldand res
42、idual thickness at various loads. These results can bereported in a graph or table.10.2.2 Calculate the compressive stress by dividing the loadat the compressive yield point by the initial horizontal cross-sectional area of the specimen.10.3 The compressive stress with the corresponding com-pressive
43、 strain shall be plotted for each test.10.4 The compressive yield point shall be reported as thearithmetic mean and minimum of the five tests.NOTE 4Not all geosynthetics exhibit a well-defined compressive yieldpoint. In such cases, if a compressive stress value is needed forcomparative purposes, use
44、 a strain value agreed upon between thepurchaser and the buyer. Such a value might be the point where there is asignificant change in the slope of the stress-strain curve, as shown by thetwo curves in Fig. 2.11. Report11.1 Report the following information:11.1.1 The description of the type of TRM te
45、sted.11.1.2 The lot or production unit represented.11.1.3 The dimensions of the test specimens.11.1.4 The test data, including: initial thickness, cross-sectional area, rate of deformation, and the deformations,strains and corresponding stresses.11.1.5 Test curves expressing the compressive load (st
46、ress)as a function of the deformation.11.1.6 The results of each specimen tested, plus the averageof the compressive yield point of the TRM, if the TRM has acompressive yield point.11.1.7 Date of test.11.1.8 Astatement of any unusual occurrences or departuresfrom the suggested procedures.11.1.9 Mach
47、ine type and date of last certification.12. Precision and Bias12.1 PrecisionThe precision of the procedure in this testmethod is being evaluated.12.2 BiasThe value of the compressive yield point ofTRMs can be defined only in terms of a test method. When thistest method is the defining method, measur
48、ements of thecompressive yield point have no bias.13. Keywords13.1 compression; deformation; geocomposite; index test;yield pointASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard ar
49、e expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a me
