ASTM_D_6773_-_08.pdf

Designation:D677308Standard Test Method forBulk Solids Using Schulze Ring Shear Tester1This standard is issued under the fixed designation D6773;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.Scope*1.1 This test method covers the apparatus and proceduresfor measuring the unconfined yield strength of bulk solidsduring both continuous flow and after storage at rest.Inaddition,measurements of internal friction,bulk density,andwall friction on various wall surfaces are included.1.2 The most common use of this information is in thedesign of storage bins and hoppers to prevent flow stoppagesdue to arching and ratholing,including the slope and smooth-ness of hopper walls to provide mass flow.Parameters forstructural design of such equipment may also be derived fromthis data.Another application is the measurement of theflowability of bulk solids,for example,for comparison ofdifferent products or optimization.1.3 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D6026.1.3.1 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 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 practice 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 analysismethods for engineering design.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.5 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:2D653 Terminology Relating to Soil,Rock,and ContainedFluidsD3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD6026 Practice for Using Significant Digits in GeotechnicalDataD6128 Test Method for Shear Testing of Bulk Solids Usingthe Jenike Shear Cell3.Terminology3.1 Definitions:For common definitions of terms in thisstandard,refer to Terminology D653.3.2 Definitions of Terms Specific to This Standard:3.2.1 adhesion test,na static wall friction test with timeconsolidation.3.2.2 angle of internal friction,i,nthe angle between theaxis of normal stress(abscissa)and the tangent to the yieldlocus.3.2.3 angle of wall friction,nthe arctan of the ratio ofthe wall shear stress to the wall normal stress.3.2.4 bin,na container or vessel for holding a bulk solid,frequently consisting of a vertical cylinder with a converginghopper.Sometimes referred to as silo,bunker or elevator.3.2.5 bulk density,b,n the mass of a quantity of a bulksolid divided by its total volume.3.2.6 bulk solid,nan assembly of solid particles handledin sufficient quantities that its characteristics can be describedby the properties of the mass of particles rather than thecharacteristics of each individual particle.It may also bereferred to as a granular material,particulate solid,or powder.Examples are sugar,flour,and ore.3.2.7 bunker,nsynonym for bin,but sometimes under-stood as being a bin without any or only a small vertical partat the top of the hopper.1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.24 on Characterizationand Handling of Powders and Bulk Solids.Current edition approved Oct.1,2008.Published November 2008.Originallyapproved in 2002.Last previous edition approved in 2002 as D6773 02.DOI:10.1520/D6773-08.2For 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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.8 consolidation,nthe process of decreasing the poros-ity of a bulk solid,which usually results in increasing itsunconfined yield strength.3.2.9 critical state,na state of stress in which the bulkdensity of a bulk solid and the shear stress in the shear zoneremain constant during shear under constant normal stress.3.