1、Designation: D 6459 07Standard Test Method forDetermination of Rolled Erosion Control Product (RECP)Performance in Protecting Hillslopes from Rainfall-InducedErosion1This standard is issued under the fixed designation D 6459; the number immediately following the designation indicates the year oforig
2、inal adoption or, 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. Scope*1.1 This test method covers the guidelines, requirementsand proce
3、dures for evaluating the ability of Rolled ErosionControl Products (RECPs) to protect hillslopes from rainfall-induced erosion. Critical elements of this protection are theability of the RECP to:1.1.1 Absorb the impact force of raindrops, thereby reduc-ing soil particle loosening through “splash” me
4、chanisms;1.1.2 Slow runoff and encourage infiltration, thereby reduc-ing soil particle displacement and transport through “overlandflow” mechanisms;1.1.3 Absorb shear forces of overland flow; and,1.1.4 Trap soil particles beneath.1.2 This test method utilizes full-scale testing procedures,rather tha
5、n reduced-scale (bench-scale) simulation, and ispatterned after conditions typically found on construction sitesat the conclusion of earthwork operations, but prior to the startof revegetation work. Therefore this considers only unveg-etated conditions.1.3 This test method provides a comparative eva
6、luation ofan RECP-to baseline bare soil conditions under controlled anddocumented conditions.1.4 The values stated in SI units are to be regarded asstandard. The values given in parentheses are mathematicalconversions to inch-pound units, which are provided forinformation only and are not considered
7、 standard.1.5 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D 6026, unless superseded by this standard.1.5.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as t
8、heindustry standard. In addition, they are representative of thesignificant digits that generally should be retained. The proce-dures used do not consider material variation, purpose forobtaining the data, special purpose studies, or any consider-ations for the users objectives; and it is common pra
9、ctice toincrease or reduce significant digits of reported data to becommensurate with these considerations. It is beyond the scopeof this standard to consider significant digits used in analyticalmethods for engineering design.1.6 This standard does not purport to address all of thesafety concerns,
10、if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Also, the user mustcomply with prevalent regulatory codes, such as OSHA (Oc-cupational
11、Health and SafetyAdministration) guidelines, whileusing the test method.2. Referenced Documents2.1 ASTM Standards:2D 653 Terminology Relating to Soil, Rock, and ContainedFluidsD 698 Test Methods for Laboratory Compaction Character-istics of Soil Using Standard Effort (12 400 ft-lbf/ft3(600kN-m/m3)D
12、3740 Practice for Minimum Requirements for AgenciesEngaged in the Testing and/or Inspection of Soil and Rockas Used in Engineering Design and ConstructionD 6026 Practice for Using Significant Digits in Geotechni-cal Data3. Terminology3.1 For common definitions of terms in this standard, referto Term
13、inology D 653.1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock; Subcommittee D18.25 on Erosion and Sediment Control Technology; and isthe direct responsibility of Section .02 on Erosion Control Blankets (ECBs).Current edition approved July 1, 2007. Published July 2007
14、. Originally approvedin 1999. Last previous edition approved in 1999 as D 6459 99.2For 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 pag
15、e onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2 Definitions of Terms Specific to This Standard:3.2.1 erosion control blanket (ECB) in erosion
16、control, nadegradable material, composed primarily of processed naturalorganic materials, manufactured or fabricated into rolls de-signed to reduce soil erosion and assist in the growth, estab-lishment and protection of vegetation.3.2.2 rolled erosion control product (RECP) in erosioncontrol, na tem
17、porary degradable or long-term non-degradable material manufactured or fabricated into rollsdesigned to reduce soil erosion and assist in the growth,establishment, and protection of vegetation.3.2.3 turf reinforcement mat (TRM), in erosion control, nanon-degradable geosynthetic or geocomposite proce
18、ssed into amatrix sufficient to increase the stability threshold of otherwiseunreinforced established vegetation.3.2.3.1 DiscussionProducts in this category may incorpo-rate ancillary degradable components to enhance the germina-tion and establishment of vegetation.4. Summary of Test Method4.1 The p
19、erformance of a rolled erosion control product inreducing rainfall-induced erosion is determined by subjectingthe material to simulated rainfall in a controlled and docu-mented environment.4.2 Key elements of the testing process include:4.2.1 Calibration of the rainfall simulation equipment;4.2.2 Pr
20、eparation of the test plot;4.2.3 Documentation of the RECP to be tested;4.2.4 Installation of the RECP;4.2.5 Performance of the test;4.2.6 Collection of runoff and associated sediment yielddata;4.2.7 Analysis of the resultant data, and;4.2.8 Reporting.5. Significance and Use5.1 This test method eval
21、uates RECPs and their means ofinstallation to:5.1.1 Reduce soil loss and sediment concentrations instormwater runoff under conditions of varying rainfall intensityand soil type, and;5.1.2 Improve water quality exiting the area disturbed byearthwork activity by reducing suspended solids.5.2 This test
22、 method models and examines conditions typi-cally found on construction sites involving earthwork activitiesincluding: highway and roads; airports; residential, commercialand industrial developments; pipelines, mines, and landfills;golf courses; etc.5.3 This test method is a performance test, but ca
23、n be usedfor quality control to determine product conformance to projectspecifications. Caution is advised since information regardinglaboratory specific precision is incomplete. For project specificconformance, unique project-specific conditions should betaken into consideration.NOTE 1The quality o
24、f the result produced by this standard isdependent on the competence of the personnel performing it, and thesuitability of the equipment and facilities used. Agencies that meet thecriteria of Practice D 3740 are generally considered capable of competentand objective testing/sampling/inspections/etc.
25、 Users of this standard arecautioned that compliance with Practice D 3740 does not itself assurereliable results. Reliable results depend on many factors; Practice D 3740provides a means of evaluating some of those factors.6. Apparatus6.1 Rainfall SimulatorsRainfall simulators shall includesprinkler
26、 heads, sprinkler risers, valves and pressure gauges.The sprinkler heads should be selected on their ability to modelnatural raindrop size and distribution (no more than 10 %greater than 6 mm (0.24 in.) and no more than 10 % smallerthan 1 mm (0.04 in.). To approximate the kinetic energy ofnatural ra
27、infall, the sprinkler riser shall be constructed toposition the sprinkler heads to achieve a minimum fall height(peak vertical trajectory) of 4.3 m (14 ft). A flow control valveand a pressure gauge capable of maintaining a uniformoperating pressure shall be located on each riser. Fig. 1 showsan exam
28、ple of a rainfall simulator.6.2 Water SourceAny water source shall be suitable forthis use provided that it does not contain deleterious materialswhich could impair the operation of the rainfall simulators.6.3 Runoff and Sediment Collection SystemThe runoff andsediment collection system includes fla
29、shing, collection appa-ratus and a holding tank. Flashing shall be fabricated to directrunoff from the plot into the collection apparatus. Once therunoff is on the flashing, it may be desirable to divert the flowto a single collection point. The flashing shall be continuousacross the entire bottom e
30、dge of the plot. A holding tank(s)capable of temporarily containing all runoff shall be connectedto the collection apparatus.6.4 Vegetative Stand Quantification EquipmentA cali-brated template used to ensure height of vegetation andcounting box are necessary for vegetated testing. Vegetation iscut t
31、o a specific, uniform stand height by placing a template onthe soil surface and trimming blades/stems at the top of thetemplate. An open, square box is used to count vegetationstems and blades to determine stand density. The box may beconstructed of metal or wood with an internal opening measure76.2
32、 mm (3 in.) square and 25.4 to 50.8 mm (1 to 2 in.) inheight.6.5 MiscellaneousOther miscellaneous equipment in-cludes: rain gauges (20), pie pans (3), sieve set (standard USsieves), evaporating dishes, a drying oven or microwave oven,balances, meteorological equipment (wind speed, temperature,precip
33、itation), a surveyors rod, sample bottles and bags, coolerand camera or video recorder.7. Procedure7.1 Test Plot Preparation:7.1.1 Construct an earthen embankment using conventionalearthwork placement techniques. Perform compaction of theembankment to create a geotechnically (structurally) stableemb
34、ankment with a surface slope of 3H:1V having a slopelength of 12 m (40 ft). Fig. 2 shows a typical embankmentcross-section.NOTE 2The effect of variations in test plot width, length, gradient,and drainage conditions are currently being evaluated.7.1.2 Plate the top surface of the embarkment with amin
35、imum 30 cm (12 in.) thick veneer of soil. General soil typesto be used for testing shall be loam, clay, and sand. Target grainD6459072sizes and plasticity indices are included in Fig. 3. Place theveneer in 15 cm (6 in.) lifts and compact to 90 6 3% ofstandard Proctor density in accordance with Test
36、MethodD 698.7.1.3 Locate test plots on the embankment using a plot sizeof 2.4 m (8 ft) in width (cross-slope) and of 12 m (40 ft) inlength (downslope). Separate the test plots such that oversprayfrom the rainfall simulators does not impact adjacent plots.NOTE 3The slope width, length and steepness w
37、ere selected as beingrepresentative of conditions typically found on construction sites. This testplot configuration was chosen to assure uniformity and consistence oftesting activities.7.1.4 Isolate the top edge and sides of each test plot by awater barrier which forms the boundary of the test plot
38、. Burythe bottom edge of the barrier approximately 10 cm (4 in.) todivert surface flow such that no intrusion of outside surfacewater onto the test plot (“run-on”) occurs. The barrier shall becontinuous such that joints do not allow outside flow to enterthe plot. Commercially available lawn edging i
39、s suitable forthis purpose.7.1.5 Loosen the soil veneer to a depth of approximately 10cm (4 in.) using a tiller or other appropriate tools. Rake thetilled plot smooth with a steel hand rake and lightly compactFIG. 1 Typical Rainfall SimulatorFIG. 2 Typical Embankment Cross SectionFIG. 3 Typical Grai
40、n Sizes and Plasticity IndicesD6459073using a turf roller. Repair depressions, voids, soft, or uncom-pacted areas before testing commences.Also, free the plot fromobstruction or protrusions, such as roots, large stones, or otherforeign material. Soil preparation methods for bare soil testingutilized
41、 as a baseline, control plots for product or vegetatedtesting shall be identical to soil preparation methods for theprotected scenario.NOTE 4Standarized, quantified soil compaction rate is being evalu-ated.7.1.6 If the plots have been used for previous test series,discard the soil carried of the plo
42、t and obliterate any rills andgullies. Spread new soil of the same type across the plot andblend (rake or till) into the surface. If the soil loss of the controlplot differs significantly from the base line calibration testreevaluate the soil properties.7.2 Calibration:7.2.1 Calibration of the rainf
43、all simulation equipment in-cludes:7.2.1.1 Rainfall intensity;7.2.1.2 Uniformity of rainfall application across the plot,and;7.2.1.3 Drop size distribution for each intensity.7.2.2 To ensure uniform distribution, do not conduct cali-bration and testing when the wind velocity is greater than 8km/h (5
44、 mph).NOTE 5Variations in wind speed and direction may affect test resultsand should be examined on a case-specific basis.7.2.3 At a minimum, conduct calibration annually or fol-lowing equipment maintenance work. Conduct one intensity/uniformity check every 90 days, or after no more than four testse
45、ries, whichever comes first.7.2.4 Place sprinkler risers around the perimeter of the testplot to provide uniform distribution. The precise location of therisers to provide uniform rainfall distribution will be deter-mined by the calibration process and the nuances of any givensimulator system (see F
46、ig. 4 for typical sprinkler riser configu-ration).7.2.5 Place the rain gauges on the plot surface following thepattern shown in Fig. 4. Duration of the calibration test shall be15 min, recorded to the nearest second. Perform calibrations atuniform pressure for each intensity. Adjust riser locations
47、untilan acceptable uniform rainfall distribution pattern is achieved,as defined in Section 8.7.2.6 Calculate the rainfall intensity uniformity using theChristiansen uniformity coefficient (see Section 8).7.2.7 To measure drop size distribution, completely fill threelabeled pie pans with sifted flour
48、, struck off with a ruler toproduce a smooth, uncompacted surface. Locate three supportsapproximately 20-cm (8-in.) high (for example, 1-gal cans)along the vertical centerline of the test plot, and at thehorizontal quarter points. Place the filled pie pans on thesupports (horizontal, not parallel to
49、 the ground) and cover. Atthe desired test intensity, remove the cover briefly so that dropsimpinge on the flour to form pellets. Recover the pans afteronly a few seconds and before the drops start to touch eachother. Repeat this procedure at each desired intensity. Air-drythe flour pellets for a minimum of 12 h. Screen each sample ofthese semi-dry pellets by emptying the entire contents of thepan onto a 70 mesh sieve to carefully remove as much looseflour as possible. Then transfer the remaining pellets toevaporating dishes and heat in an oven at approximately 43C
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