1、Designation:C1609/C1609M12Standard Test Method forFlexural Performance of Fiber-Reinforced Concrete(UsingBeam With Third-Point Loading)1This standard is issued under the fixed designation C1609/C1609M;the number immediately following the designation indicates theyear of original adoption or,in the c
2、ase of revision,the year of last revision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method evaluates the flexural performance offiber-reinforced concrete using paramete
3、rs derived from theload-deflection curve obtained by testing a simply supportedbeam under third-point loading using a closed-loop,servo-controlled testing system.1.2 This test method provides for the determination offirst-peak and peak loads and the corresponding stressescalculated by inserting them
4、 in the formula for modulus ofrupture given in Eq 1.It also requires determination of residualloads at specified deflections,the corresponding residualstrengths calculated by inserting them in the formula formodulus of rupture given in Eq 1(see Note 1).It provides fordetermination of specimen toughn
5、ess based on the area underthe load-deflection curve up to a prescribed deflection(seeNote 2)and the corresponding equivalent flexural strengthratio.NOTE1Residual strength is not a true stress but an engineering stresscomputed using simple engineering bending theory for linear elasticmaterials and g
6、ross(uncracked)section properties.NOTE2Specimen toughness expressed in terms of the area under theload-deflection curve is an indication of the energy absorption capabilityof the particular test specimen,and its magnitude depends directly on thegeometry of the test specimen and the loading configura
7、tion.1.3 This test method utilizes two preferred specimen sizesof 100 by 100 by 350 mm 4 by 4 by 14 in.tested on a 300 mm12 in.span,or 150 by 150 by 500 mm 6 by 6 by 20 in.tested on a 450 mm 18 in.span.A specimen size differentfrom the two preferred specimen sizes is permissible.1.4 UnitsThe values
8、stated in either SI units or inch-pound units are to be regarded separately as standard.Thevalues stated in each system may not be exact equivalents;therefore,each system shall be used independently of the other.Combining values from the two systems may result in non-conformance with the standard.1.
9、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 Documen
10、ts2.1 ASTM Standards:2C31/C31M Practice for Making and Curing Concrete TestSpecimens in the FieldC42/C42M Test Method for Obtaining and Testing DrilledCores and Sawed Beams of ConcreteC78 Test Method for Flexural Strength of Concrete(UsingSimple Beam with Third-Point Loading)C125 Terminology Relatin
11、g to Concrete and Concrete Ag-gregatesC172 Practice for Sampling Freshly Mixed ConcreteC192/C192M Practice for Making and Curing Concrete TestSpecimens in the LaboratoryC823 Practice for Examination and Sampling of HardenedConcrete in ConstructionsC1140 Practice for Preparing and Testing Specimens f
12、romShotcrete Test Panels3.Terminology3.1 DefinitionsThe terms used in this test method aredefined in Terminology C125.3.2 Definitions of Terms Specific to This Standard:3.2.1 end-point deflection,nthe deflection value on theload-deflection curve equal to1150of the span length,or alarger value as spe
13、cified at the option of the specifier of tests.3.2.2 first-peak load,P1,nthe load value at the first pointon the load-deflection curve where the slope is zero.3.2.3 first-peak deflection,1,nthe net deflection value onthe load-deflection curve at first-peak load.1This test method is under the jurisdi
14、ction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.42 on Fiber-Reinforced Concrete.Current edition approved Dec.1,2012.Published January 2013.Originallyapproved in 2005.Last previous edition approved in 2010 as C1609/C1609M 10.DOI:10.15
15、20/C1609_C1609M-12.2For 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 en
16、d of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.4 first-peak strength f1,nthe stress value obtainedwhen the first-peak load is inserted in the formula for modulusof rupture given in Eq 1.3.2.5 load-deflection curve,nthe plot of load versus netdeflection of a flexural beam specimen loaded to the end-pointdeflection.3.2.6 net deflection,nthe deflection measured at mid-spanof a flexural beam specimen exclusive of an