1、Designation: D 7101 08Standard Index Test Method forDetermination of Unvegetated Rolled Erosion ControlProduct (RECP) Ability to Protect Soil from Rain Splash andAssociated Runoff Under Bench-Scale Conditions1This standard is issued under the fixed designation D 7101; the number immediately followin
2、g the designation indicates the year oforiginal 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 index test me
3、thod establishes the guidelines, re-quirements and procedures for evaluating the ability of unveg-etated rolled erosion control products (RECPs) to protect soilsfrom simulated rainfall (rain splash) and minimal runoffinduced erosion. The critical element of this protection is theability of the unveg
4、etated RECP to absorb the impact force ofraindrops, thereby reducing soil particle loosening through“splash” mechanisms, and limiting the ability of runoff to carrythe loosened soil particles.1.2 This index test method utilizes bench-scale testingprocedures and is not indicative of unvegetated RECP
5、perfor-mance in conditions typically found in the field.NOTE 1The values obtained with this bench scale procedure are forinitial performance indication, general product comparison and conform-ance purposes only. These values should not be used in estimating RECPsoil protection in actual field use wi
6、th such calculations as the UniversalSoil Loss Equation (USLE) or Revised Universal Soil Loss Equation(RUSLE) without verification from qualified, large-scale tests.1.3 This index test is not intended to replace full-scalesimulation or field testing in acquisition of performance valuesthat are requi
7、red in the design of erosion control measuresutilizing unvegetated RECPs.1.4 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.5 All observed and calculated values shall conform to theguidelines for significant digits and round
8、ing established inPractice D 6026, unless superseded by this standard.1.5.1 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as theindustry standard. In addition, they are representative of thesignificant digits that generally should be retai
9、ned. 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 practice toincrease or reduce significant digits of reported data to becommensurate with these considerations. It is
10、 beyond the scopeof this index test method to consider significant digits used inanalytical methods for engineering design.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use and may involveuse of hazardous materials, equipment, and operations. It
11、 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 Health and Safety Administration) g
12、uidelines, whileusing the index 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 6026 Practice for Using Sign
13、ificant Digits in Geotechni-cal DataD 3740 Practice for Minimum Requirements for AgenciesEngaged in the Testing and/or Inspection of Soil and Rockas Used in Engineering Design and ConstructionD 6459 Test Method for Determination of Rolled ErosionControl Product (RECP) Performance in Protecting Hills
14、-lopes from Rainfall-Induced ErosionD 6475 Test Method for Measuring Mass Per Unit Area ofErosion Control BlanketsD 6566 Test Method for Measuring Mass per Unit Area ofTurf Reinforcement Mats3. Terminology3.1 Definitions: For common definitions of terms in thisstandard, refer to Terminology D 653.1T
15、his test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.25 on Erosion andSediment Control Technology.Current edition approved Jan. 1, 2008. Published February 2008. Originallyapproved in 2007. Last previous edition approved
16、in 2007 as D 7101 07.2For 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 website.1*A Summary of Changes section appears a
17、t the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Summary of Test Method4.1 Soil cores consisting of containers with both bare andunvegetated RECP-protected soil are exposed to simulatedrainfall.4.2 The amo
18、unt of soil that splashes out of or is dislodgedand carried by runoff from the containers is collected andweighed. The results can be used to compare bare andRECP-protected situations.4.3 Key elements of the testing process include: 1) calibra-tion of the rainfall simulation equipment; 2) preparatio
19、n of thetest cores; 3) documentation of the RECP to be tested; 4)installation of the RECP; 5) prosecution of the test; 6)collection of data; 7) analysis of the resultant data, and; 8)reporting.5. Significance and Use5.1 This index test method indicates a unvegetated RECPsability to reduce rainsplash
20、-induced erosion under bench-scaleconditions. This test method may also assist in identifyingphysical attributes of RECPs that contribute to their erosion-control performance.5.2 This test method is bench-scale and therefore, appropri-ate as an index test for initial indication of product perfor-man
21、ce, for general comparison of unvegetated RECP capabili-ties, and for product quality assurance/conformance testing.The results of this test are not indicative of an RECPs actualfield performance.NOTE 2The quality of the result produced by this standard isdependent on the competence of the personnel
22、 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. Users of this standard arecautioned that compliance with Practice D 3740 does not it
23、self assurereliable results. Reliable results depend on many factors; Practice D 3740provides a means of evaluating some of those factors.6. Apparatus6.1 Rainfall SimulatorRainfall is produced by a labora-tory simulator capable of creating uniform drops with a mediandiameter of 3.0 to 3.5 mm (0.12 t
24、o 0.14 in.) from a drop heightof 2000.0 mm (78.72 in.) above the lowest point of the inclinestructure (see 6.3). The rainfall simulator shall be capable ofproducing rainfall intensities of 51 6 5 mm/hr (2 6 0.2 in./hr),102 6 5 mm/hr (4 6 0.2 in./hr), and 153 6 5 mm/hr (6 6 0.2in./hr). The simulator
25、must be centered over the test area toprovide uniform rain application over the entire incline struc-ture (Fig. 1).6.2 Soil CoresConsist of water-tight containers nominally200 6 10 mm (8 6 0.4 in.) inside diameter plastic pipe sectionFIG. 1 Slope Erosion: Bench Scale Laboratory Test ApparatusD710108
26、2cylinders with height of 100 6 10 mm (4 6 0.4 in.) holdingsoil and test specimens.6.3 Incline StructureRequired is an incline structure com-prised of three adjacent “runoff ramps” each having an openingat its lower end to accommodate a recessed soil core. Theramps shall be 900 6 20 mm (35 6 0.8 in.
27、) in length and 2506 20 mm wide (10 6 0.8 in.). The incline structure shall beadjustable to a slope gradient of at least 3:1 (horizontal:verti-cal) and be able to maintain the desired slope. The inclinestructure shall have raised dividers (at least 25.0 mm (1 in.)tall) between ramps to prevent cross
28、-ramp soil splash andrun-on/runoff (Fig. 1).6.4 Collection BucketsAny type of bucket having suffi-cient diameter and volume to collect all runoff from the runofframp may be used.6.5 FiltersWhatman #3 filter paper3to separate sedimentfrom soil and water solution.6.6 MiscellaneousOther miscellaneous e
29、quipment in-cludes: sieve set (standard US sieves), evaporating dishes,drying oven, and balance.7. Sampling7.1 The laboratory sample should be 1 m2(10.76 ft2).8. Procedure8.1 Calibration of Rainfall Simulator8.1.1 Calibration of the rainfall simulation equipment in-cludes verification of: 1) rainfal
30、l intensity; 2) uniformity ofrainfall application across the holding container, and; 3) dropsize. See Annex A1 for details.8.1.2 At a minimum, calibration shall be conducted on anannual basis and also following initital equipment set-up andany equipment maintenance.8.2 Test Set-up8.2.1 After calibra
31、tion, prepare three soil cores for eachRECP to be tested and nine cores for the bare soil conditions.8.2.1.1 Fill/compact (see 8.2.1.2) the cores with the stan-dard soil (seeAnnexA2 for soil details) flush with the lip of thecontainer.NOTE 3The standard sand used in this test procedure has been foun
32、dto be successful for product comparison purposes. However, site-specificsoils, user-defined soils, or both, may be used based on user needs. Ifnon-standard soils are used, agreement should be established between thetesting laboratory and the test user.8.2.1.2 Unless otherwise agreed to prior to tes
33、ting, compactthe soil into the soil cores at 90 6 3% of standard dry densityat optimum moisture content 6 2%.8.2.2 Adjust the incline structure to a gradient of 3:1 (h:v),unless other slope gradient(s) are agreed to between the testlaboratory and the user of the test.8.2.3 Place three of the prepare
34、d soil cores into the openingsof the incline structure. The top edges of the cores are to be aminimum of 2 cm (0.8 in) away from the sides of the runofframps.8.2.4 For RECP-protected cores, place the RECP testsample over the entire incline structure including the soil coresurfaces. Clip or otherwise
35、 affix the sample to the raisedbarriers between runoff ramps in such a way to avoid obstruc-tion of flow and facilitate intimate contact with the runoff rampand the soil surfaces of the cores.8.2.4.1 Each RECP specimen shall be weighed and mea-sured to determine its mass per unit area in accordance
36、withTest Methods D 6475 and D 6566 prior to affixing to the runofframps.8.3 Test Operation and Data Collection8.3.1 Cover the incline structure and soil cores with awaterproof lid or canopy and activate rainfall simulator at thetarget intensity. Both the RECP protected and bare soil controlcores sha
37、ll be subjected to three target rainfall intensities of 516 5 mm/hr (2 6 0.2 in./hr), 102 6 5 mm/hr (4 6 0.2 in./hr),and 153 6 5 mm/hr (6 6 0.2 in./hr), unless other intensities areagreed upon between the user of the test and testing laboratory.8.3.2 After rainfall reaches a steady rate, position th
38、ecollection buckets at the end of the runoff ramps and removethe cover from the incline structure and begin timing the test.8.3.3 After five minutes, replace the waterproof cover orturn off the rainfall and take the collection buckets out of thesimulator.8.3.4 Position empty collection buckets at th
39、e end of therunoff ramps, remove the cover or turn rainfall back on, andresume the test.8.3.5 Repeat 8.3.3 and 8.3.4 every 5 min.8.3.6 Pour the water and soil mixture from the collectionbuckets through a Whatman #3 filter paper to collect thesediment from the first five minutes of the test. Measure
40、andrecord the amount of water collected in each bucket.Additionalwater may be used in order to wash all the soil out of theholding container.8.3.7 Repeat this process until the set of three soil cores hasundergone six five-minute periods of simulated rainfall, whichequals 30 min of exposure to simul
41、ated rain.8.3.8 Dry each sediment sample in an oven at 105C(221F) for a minimum of 24 h, then weigh sample anddetermine mass to 6 0.01 g. The data for each pot should beentered into a table such as shown in Fig. 2.8.3.9 Repeat the procedure with the remaining sets of threetest cores at each target r
42、ainfall intensity.9. Calculation9.1 Average the three masses of sediment corresponding tothe same five-minute period(s) to obtain six mean masses ofsoil loss from the RECP-protected cores at each target rainfallintensity.9.1.1 The data for each pot should be entered into a tablesuch as shown in Fig.
43、 2 and normalized to the sample rollaverage mass per unit area based on the specimen-specificmass per unit area for the pot.3The sole source of supply of the apparatus known to the committee at this timeis Whatman Inc., 200 Park Ave., Suite 210, Florham Park, New Jersey, 07932,. If you are aware of
44、alternative suppliers, please provide thisinformation to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee,1whichyou may attend.D7101083FIG.2ExampleofTableDataD71010849.2 Sum the six mean masses of soil loss from the
45、RECP-protected soil cores to obtain the mean mass (MRECP) for theentire 30 min run at each rainfall intensity.9.3 Average the three masses of sediment corresponding tothe same five-minute period(s) to obtain six mean masses ofsoil loss from the bare soil cores at each target rainfall intensity.9.4 S
46、um the six mean masses of soil loss from the bare soilcontrol cores to obtain the mean mass (Mcontrol) for the entire30 min run at each target rainfall intensity.9.5 Enter the mean masses obtained for the RECP and baresoil control cores as a function of time at each target rainfallintensity into a t
47、able.9.6 Calculate the Bench-Scale Cover Index (BSCI) of thetest material at each rainfall intensity as follows:BSCI 5 MRECP /MCONTROL(1)where:MRECP= mean mass of soil loss from RECP pro-tected cores according to 9.2, andMCONTROL= mean mass of soil loss from unprotectedcontrol cores according to 9.4
48、.9.7 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D 6026, unless superseded by this standard.10. Report10.1 The report shall at a minimum include the following:10.1.1 General information, including test facility location
49、,date, time and operator name.10.1.2 Calibration data and analysis (latest information).10.1.3 Test set-up activities, including 1) test conditions(slope gradient, rainfall intensity); 2) soil type and conditions;3) RECP product type and description, and; 4) soil loss (g).10.1.3.1 The sand gradation and standard proctor moisture-density relationship shall be reported. If other soils are used,the soils information shall include: soil type/texture (that is,topsoil, sandy loam, silt loam, clay); standard proctor moisture-density relationship; gradation (i
