1、Designation: D 7351 07Standard Test Method forDetermination of Sediment Retention Device Effectivenessin Sheet Flow Applications1This standard is issued under the fixed designation D 7351; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revi
2、sion, 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. Scope1.1 This test method establishes the guidelines, require-ments and procedures for evaluating the abilit
3、y of SedimentRetention Devices (SRDs) to retain sediment when exposed tosediment-laden water “sheet” flows.1.2 This test method is applicable to the use of an SRD as avertical permeable interceptor designed to remove suspendedsoil from overland, nonconcentrated water flow. The functionof an SRD is t
4、o trap and allow settlement of soil particles fromsediment laden water. The purpose is to reduce the transport oferoded soil from a disturbed site by water runoff.1.3 The test method presented herein is intended to indicaterepresentative performance and is not necessarily adequate forall purposes in
5、 view of the wide variety of possible sedimentsand performance objectives.1.4 The values stated in SI units are to be regarded asstandard. The inch-pound values given in parentheses areprovided for information purposes only.1.5 All observed and calculated values shall conform to theguidelines for si
6、gnificant digits and rounding established inPractice D 6026.1.5.1 The procedures used to specify how data are collected/recorded and calculated in this standard are regarded as theindustry standard. In addition, they are representative of thesignificant digits that should generally be retained. The
7、proce-dures used do not consider material variation, purpose forobtaining the data, special purpose studies, or any consider-ation for the users objectives; and it is common practice toincrease or reduce significant digits of reported data to com-mensurate with these considerations. It is beyond the
8、 scope ofthis standard to consider significant digits used in analysismethods for engineering design.1.6 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 hea
9、lth practices and determine the applica-bility of regulatory limitations prior to use.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
10、(600kN-m/m3)D 3740 Practice for Minimum Requirements for AgenciesEngaged in the Testing and/or Inspection of Soil and Rockas Used in Engineering Design and ConstructionD 5141 Test Method for Determining Filtering Efficiencyand Flow Rate of a Geotextile for Silt Fence ApplicationUsing Site-Specific S
11、oilD 6026 Practice for Using Significant Digits in Geotechni-cal Data3. Terminology3.1 For definitions of terms used in this test method, seeTerminology D 653.4. Summary of Test Method4.1 Sediment-laden water is allowed to “sheet flow” up toand seep through, over, and/or under an installed sedimentr
12、etention device (SRD). At a minimum, the amount (via waterand soil weight) of sediment-laden flow is measured bothupstream and downstream of the SRD.1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.25 on Erosion and
13、Sediment Control Technology.Current edition approved May 1, 2007. Published June 2007.2For 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
14、 page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2 The measurement of sediment that passes through, over,and/or under the SRD compared to the amount in the upstreamflow is used to quantify the effectiveness
15、of the SRD inretaining sediments3,4.5. Significance and Use5.1 This test method quantifies the ability of a sedimentretention device (SRD) to retain eroded sediments caused bysheet flowing water under full-scale conditions. This testmethod may also assist in identifying physical attributes ofSRDs th
16、at contribute to their erosion control performance.5.2 The effectiveness of SRDs is installation dependent.Thus, replicating field installation techniques is an importantaspect of this test method. This test method is full-scale andtherefore, appropriate as an indication of product performance,for g
17、eneral comparison of product capabilities, and for assess-ment of product installation techniques.NOTE 1Test Method D 5141 is an alternate test method for evaluatingsediment retention device effectiveness, if it is not necessary to simulatefield installation conditions.NOTE 2The quality of the resul
18、t 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/inspection/etc. Users of th
19、is standard arecautioned that compliance with Practice D 3740 does not in itself assurereliable results. Reliable results depend on many factors: Practice D 3740provides a means of evaluating some of those factors.6. Apparatus6.1 Equipment required. (See Fig. 1, Fig. 2)6.1.1 Combination mixing tank
20、and scale A tank with aninternal paddle mixer device mounted on scales capable ofholding/weighing 4500 kg of sediment-laden water.6.1.2 A clean water source and pumping equipment Asource of water and associated pumping equipment sufficient torepeatedly fill the mixing tank in a timely manner.6.1.3 A
21、 consistent soil stockpileA stockpile of soil insufficient quantity to both create sediment-laden water and tocreate/replace subgrade in the installation zone. The generalsoil type to be used for testing shall be loam with target grainsizes and plasticity index as shown in Table 1, unless otherwises
22、pecified.6.1.4 A loader for moving the soil to the mixerAfront-endloader of sufficient reach and capacity to dump a prescribedamount of soil into the mixing tank.6.1.5 A variable discharge apparatus from the mixer Avariable discharge apparatus from the mixer A valve-controlled discharge hose that al
23、lows for controlled, uniformdischarge from the mixing tank.6.1.6 Soil and water sampling equipment Sampling jars(at least 12 per test) for taking “grab” samples periodicallyduring the test.6.1.7 Excavating/compacting machinery for cleaning andpreparing the test area Earthmoving and compactingequipme
24、nt is needed to prepare/replace the soil in the installa-tion zone.6.1.8 A scaled collection system adequate to handle thereleased runoff A tank mounted on scales of sufficientvolume to collect all runoff passing the SRD.6.2 Retention Area:6.2.1 A non-permeable, smooth, 3:1 slope surface (at least 5
25、m long) immediately below the mixer discharge shall beprovided to spread the discharge to the width of the retentionzone (length of the SRD installation) and to provide a retentionzone above the installation zone.6.2.2 An installation zone approximately 2 m wide by theintended length of the SRD inst
26、allation (typically 20 ft)comprised of prepared soil subgrade to allow full-scale instal-lation of the SRD to be tested.6.2.3 The center of the installed SRD should be placed inthe center of the installation zone each time to replicate heightof water as it relates to volume retained.3Sprague, C.J. (
27、2004), “Testing the Effectiveness of Sediment Retention De-vices”, StormCon 04, Palm Desert, CA, (digital proceedings).4Sprague, C.J. and Carpenter, T. (2004), “A New Procedure for Testing theEffectiveness of Sediment Retention Devices”, Conf. XXXV, International ErosionControl Assoc., Philadelphia,
28、 pp. 265-275.FIG. 1 Schematic (Plan) DiagramD73510726.2.4 The prepared soil subgrade will be compromised eachtest, so it will have to be reconstructed after each test.6.2.5 The area below the installation zone should be non-permeable to facilitate efficient transmission of runoff passingthe SRD to t
29、he collection tank.6.3 The Collection Area:6.3.1 The collection tank shall be at a lower grade than theinstallation area so that runoff passing the SRD will efficientlyflow via gravity into the tank. A retaining wall between theinstallation zone and the collection tank is recommended. Thearea betwee
30、n the retaining wall and the installed SRD shouldbe impermeable, and so facilitate collection of sedimentsdeposited after passing the SRD but before entering thecollection tank.7. SRD Installation7.1 A representative sample of the SRD to be tested shall beused.7.2 The SRD sample shall be installed i
31、n accordance withthe manufactures recommendations or, lacking recommenda-tions, in accordance with generally accepted constructionprocedures, including orientation perpendicular to flow withappropriate trenching and/or staking.8. Procedure8.1 SRD Installation:8.1.1 Prepare the installation zone usin
32、g the same soil to beused as sediment, unless otherwise agreed with the client. Thesoil shall be placed to a depth in excess of the depth ofinstallation and compacted to 90 6 3% of Standard Proctordensity, at a soil moisture within 63 % of optimum moisturecontent per Test Method D 698. , unless othe
33、rwise requested bythe client. The installation zone should be wide enough toaccommodate the desired length of SRD. Unless otherwiseagreed with the client, the SRD length exposed to flow betweenend abutments shall be sufficient to completely contain the testflow, but no more than the 7 m.8.2 Mixing,
34、Releasing, and Collecting Sediment-Laden Run-off:8.2.1 Procure soil as described in 6.1.3 in adequate quanti-ties for the testing process, determine its characteristics forfuture replication needs, and cover to prevent contaminationand rainfall degradation.8.2.2 Create sediment-laden runoff by combi
35、ning water andsoil in the mixing tank and maintain agitation during the test.Unless otherwise directed by the client, 2270 kg of water and136 kg of soil shall be combined to create the sediment-ladenrunoff. This amount of water and sediment simulates sheet flowfrom a slope measuring 6.1 m wide by 30
36、 m long exposed tothe peak 30 min of a 100 mm per hour rainfall hydrograph.NOTE 3An important variable in any testing procedure is the estab-lishment of test “conditions”. For a sediment control performance test thismeans selecting an appropriate design storm event and associated runoffalong with an
37、 expected amount of sediment to be transported by therunoff. For this testing, a standard 10-y, 6-h storm event (mid-Atlanticregion of US) was selected. This return frequency is commonly used forsizing sediment control ponds and, thus, was deemed appropriate for thetesting of other SRDs. Using this
38、criterion, a 100 mm (4 in) rainfall wasselected. It was also assumed that approximately 25% of the storm wouldoccur during the peak 30 minutes, and that 50% of the rainfall wouldinfiltrate into the ground. (Goldman, et al, 1986)Atheoretical contributoryarea of 30 m (100 ft) slope length by 6 m (20 f
39、t) wide was selected to limitrunoff to sheet flow conditions. (Richardson, 1990). Runoff and associatedsediment were calculated using the Modified Universal Soil Loss Equation(MUSLE) which allows for calculating a storm-specific quantity ofsediment. Following is the MUSLE (SI formula):T 5 89.6 VxQp!
40、0.56 KLSCPwhere:T = sediment yield (tonnes);V = runoff (m3) = (Rainfall Infiltration) x Area;O = peak flow (m3/s)K, LS, C, P = P are from RUSLE chartsThe following calculations provided the runoff and sediment load usedin the testing:V 5 0.5!* x 0.1 m! x 180 m2! 5 9 m3where:Qp= (0.1m) x (0.25)* x (0
41、.5)* x (180m2) = 2.25 m3/30min = 0.00125 m3/s (* = 25% of storm during30-min peak; * = 50% infiltration)FIG. 2 Example of Data Table for TestingTABLE 1 Target Grain Sizes and Plasticity IndicesLoam ClayD100(mm) D10025D85(mm) 0.5 D855.0D50(mm) 0.001 D501.0D15(mm) 0.005 D15Plasticity Index 1 PI 8D7351
42、073K, sandy-silt = 0.041; LS, 2-10%/30m = 0.46 (approx); C, P = 1.0T = 89.6 (9 x 0.00125)0.56(0.041) (0.46) (1.0) (1.0) =0.136 Tonnes = 136 kg of soil (assume most sedi-ment is generated during the peak flow period)Test Quantities: 30-Minute Runoff: 2.25 m3x 1000 kg/m3= 2250 kg(approx. 5000 lb) Sedi
43、ment Load: 136 kg (approx. 300 lb)5, 68.2.3 Discharge volume evenly for 30 min. Measure thequantity of released runoff at no less than 5-min intervals bynoting the reduction in weight in the mixing tank. Adjust thevalve on the outlet hose to increase/decrease flow to stay asclose as possible to the
44、target (2700 kg / 30 min = 90 kg / min).Maintaining a relatively steady and accurate flow rate isimportant, as the calculations will assume that this flow rate isconstant. The retention area construction and mixing tankdischarge should combine to cause the flow to spread out toimpact the full length
45、 of the SRDNOTE 4Larger flow rates than defined in 8.2.2may not result in sheetflow impacting the SRD. If this occurs this test method is not appropriate8.2.4 As runoff passing the SRD enters the collection tank,record the weight of the collection tank, and take grab samplesof runoff entering the ta
46、nk, at 5 min intervals.8.2.5 Cutoff time is 90 min, unless otherwise directed by theclient. An earlier cutoff time is acceptable when there islow-volume ponding and minimal discharge.8.3 Data Collection:8.3.1 Grab SamplesCollect grab samples at 5 min inter-vals at the mouth of the discharge from the
47、 mixing tank andfrom a suitable downstream (between the installed SRD andthe collection tank) location. Collect all samples in the samesize container (250 ml bottles are recommended) and in thesame manner. Pre-mark each container and do not overfill oroverrun the sample bottle. Concentrations may be
48、 small, thuspoor sampling techniques may significantly affect results.Multiple measurements cause a hectic pace, so pre-markingand immediately recording insures consistency and accuracy.8.3.2 Tank Measurements Sediment-laden water in boththe mixing and collection tanks is primarily measured byweight
49、.8.3.3 ObservationsMake and record visual observationsrelevant to the testing, such as height of the SRD, the depth ofponding (maximum depth and depth at end of test), undermin-ing, overtopping, catastrophic product/system failure, etc. andthe associated times. It is important to document the progres-sion of undermining flows and associated times. Photographicand video documentation is preferred.8.3.4 Time RecordsRecord the time of each grab sample,each tank and ponding depth measurement, and the time toreach zero ponding height, if reached within the ti
