ASTM_D_7880_-_D_7880M_-_13.pdf

Designation:D7880/D7880M13Standard Test Method forDetermining Flow Rate of Water and Suspended SolidsRetention from a Closed Geosynthetic Bag1This standard is issued under the fixed designation;the number immediately following the designation indicates the year of originaladoption or,in the case of revision,the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method is used to determine the flow rate ofwater and suspended solids through a geosynthetic permeableclosed bag used to contain high water content slurry such asdredged material.1.2 The results for the water and sediment that pass throughthe geotextile bag are shown as liters of water per time period,and the percent total suspended solids in milligrams per liter orparts per million.1.3 The flow rate is the average rate of passage of a quantityof solids and water through the bag over a specific time period.1.4 This test method requires several pieces of specifiedequipment such as an integrated water sampler,analyticalbalance,geotextile bag,stand clear PVC pipes,testing frame,and clean containers to collect the decant water and a repre-sentative sample of high water content material from theproposed dredge area or slurry source.1.5 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.Combiningvalues from the two systems may result in non-conformancewith the standard.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 health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD653 Terminology Relating to Soil,Rock,and ContainedFluidsD4354 Practice for Sampling of Geosynthetics and RolledErosion Control Products(RECPs)for TestingD4439 Terminology for Geosynthetics3.Terminology3.1 Definitions:3.1.1 Fordefinitionsofothertermsrelatingtogeosynthetics,refer to Terminology D4439.3.1.2 For definitions of textile terms,refer to TerminologyD123.3.1.3 For definitions of soil terms,refer to TerminologyD653.3.1.4 high water content material,na slurry of water andsolids exhibiting the properties of a liquid,typically having apercent solids by weight smaller than 50%(water contentgreater than 100%),and the size of the solid particles tend tobe very fine grained(0.064 mm).3.2 Definitions of Terms Specific to This Standard:3.2.1 flow rate,nvolume of fluid per unit time,expressedas an average,that passes through a geotextile hanging bag.3.2.2 geotextile hanging bag,nbag,tube,sock,or con-tainer designed and fabricated from a single or a combinationof layers of permeable geosynthetic to retain finegrainedparticles such as found in dredged material,for subsequentdewatering of the contained semi fluid materials.4.Summary of Test Method4.1 A geotextile bag is constructed by sewing one or morelayers of geotextiles together to form a closed container with anentry clear PVC pipe providing entry to the bag.The bag willsupport and contain a measured amount of saturated dredgedmaterial or other high water content material.4.2 The amount of water and sediment that flows throughthe geotextile container is collected at given time intervals andmeasured.The amount of sediment passing the geotextilecontainer is determined as the total suspended solids.4.3 Use material from the designated area to be dredged atthe estimated initial percent solids as the actual fieldconditions,or the source of the high water content material.1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.03 on Perme-ability and Filtration.Current edition approved July 1,2013.Published July 2013.DOI:10.1520/D7880_D7880M132For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Significance and Use5.1 This test method may be used as an aid to designgeotextile container systems that contain fine-grained,highwater content slurries such as dredged materials to meet specialenvironmental or operational requirements.This test is oftenused to demonstrate the efficacy of geotextile dewatering toregulatory agencies in determining the amount of dredgedmaterial sediment passing through a geotextile and the flowrate for specific high water content materials.5.2 The designer can use this test method to assess thequant