ASTM_D_7497_-_09.pdf

Designation:D749709Standard Practice forRecovering Residue from Emulsified Asphalt Using LowTemperature Evaporative Technique1This standard is issued under the fixed designation D7497;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 practice covers a method for recovering the residuefrom emulsified asphalts such as those specified in D977 andD2397 using a low temperature evaporative technique that issimilar to pavement conditions.The recovered residue can beused for further testing as required.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.3 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:2D977 Specification for Emulsified AsphaltD2397 Specification for Cationic Emulsified AsphaltD6934 Test Method for Residue by Evaporation of Emulsi-fied AsphaltD6997 Test Method for Distillation of Emulsified Asphalt2.2 Other Standard:NF EN 13074 Recovery of Binder from Bitumen Emulsionsby Evaporation33.Significance and Use3.1 The procedure described in this practice is used toobtain a residue from an emulsified asphalt that may be usedfor further testing in devices such as a dynamic shear rheom-eter.The lower evaporative temperatures of this procedureprovide conditions that are very close to that of applicationtechniques for these materials.This practice could be used inplace of recovery techniques such as those of D6934 andD6997,when the temperatures used in those standards wouldnegatively affect the residue.4.Reagents and Materials4.1 Silicone MatThe mat used can be similar to thatspecified in NF EN 13074 or any mat that will allow anemulsified asphalt spread rate of 1.52.0 kg/m2.The mat mayhave a lip to contain the emulsified asphalt to the appropriatearea.NOTE1A silicone mat can be purchased at various restaurant supplystores and a good size for this application is a half-sheet pan size to fit inmost laboratory ovens.4.2 SpatulaPalette knife or other suitable material forspreading the emulsified asphalt.4.3 Forced Draft OvenCapable of maintaining a tempera-ture of 25C 6 2C and 60C 6 2C.The racks should be ableto be spaced a minimum of 10 cm from the top and bottom ofthe oven and with a spacing of a minimum of 4 cm betweenracks with samples.The oven racks must be checked for level,with a bubble level of 250 mm minimum length,from side toside and front to back of the oven.5.Procedure5.1 Pour the required amount of emulsified asphalt onto thesilicone mat and spread evenly with a spatula to give a spreadrate of 1.5 kg/m2to 2.0 kg/m2of emulsified asphalt.Thesilicone mat should be supported by an oven tray or other flattray or pan that will allow easy transfer to an oven.Table 1 maybe used as a guide for the quantities of emulsified asphaltnecessary to give the appropriate spread rate for a given area.5.2 Place the silicone mat with the emulsified asphalt into a25C 6 2C forced draft oven for 24 hours 6 1 hour.5.3 Transfer the silicone mat with the emulsified asphalt toa 60C 6 2C forced draft oven for 24 hours 6 1 hour.5.4 Remove the silicone mat with the emulsified asphaltresidue from the 60C oven and allow to cool at ambient labconditions for one hour prior to removal from the mat.1This practice is under the jurisdiction of ASTM Committee D04 on Road andPaving Materials and is the direct responsibility of Subcommittee D04.42 onEmulsified Asphalt Test.Current edition approved Jan.1,2009.Published January 2009.DOI:10.1520/D7497-09.2For 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.3Available from AFNOR(French Standard Institute),11,rue Francis dePressens 93571 La Plaine Saint-Denis Cedex,France,http:/www.afnor.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.5 Carefully peel the emulsified asphalt residue from themat using a wooden or plastic utensil to not damage thesilicone mat.The residue can be kneaded into the appropriatesample size for testing(see 3.1)if appropriate gloves are wornto not allow skin contact with the residue.NOTE2For softer binders it may be necessary to cool the mat andresidue in a refrigerator prior to removal.NOTE3Examples of a wooden or plastic utensil may be a tonguedepressor,silicone spatula,or plastic knife.NOTE4The recovered binder may be stored in a se