ASTM_D_7701_-_11.pdf

Designation:D770111Standard Test Method forDetermining the Flow Rate of Water and Suspended Solidsfrom a Geotextile Bag1This standard is issued under the fixed designation D7701;the number immediately following 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()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 permeablebag used to contain high water content slurry such as dredgedmaterial.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 container,frame to hold the geotextilecontainer,and clean containers to collect the decant water anda representative sample of high water content material from theproposed dredge area or slurry source.1.5 The values stated in SI units are to be regarded as thestandard.The values in parentheses are provided for informa-tion only.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 GeosyntheticsD4759 Practice for Determining the Specification Confor-mance of Geosynthetics3.Terminology3.1 Definitions:3.1.1 Fordefinitionsofothertermsrelatingtogeosynthetics,refer to Terminology D44393.1.2 For definitions of textile terms,refer to TerminologyD1233.1.3 For definitions of soil terms,refer to TerminologyD6533.1.4 high water content material,n-a 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 to bevery 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 fine-grainedparticles 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 container that willsupport and contain a measured amount of saturated dredgedmaterial or other high water content material.4.1.1 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.4.2 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 Oct.1,2011.Published October 2011.DOI:10.1520/D7701112For 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 thequantity of fine-grained dredged material sediment that maypass through the geotextile container into the environment.5.3 This test method is intended for evaluation of a specificmaterial,as