ASTM_C_917_-_05_2011.pdf

Designation:C91705(Reapproved 2011)Standard Test Method forEvaluation of Cement Strength Uniformity From a SingleSource1This standard is issued under the fixed designation C917;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 intended for use in instances inwhich the purchaser desires information on the strength uni-formity of a hydraulic cement produced at a single source.It isintended that this test method normally be used for thepredominant cement manufactured at a cement plant.Guide-lines for sampling,testing,presentation of results,and evalu-ation are given.1.2 The values stated in inch-pound units are to be regardedas the standard.The values 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:2C109/C109M Test Method for Compressive Strength ofHydraulic Cement Mortars(Using 2-in.or 50-mm CubeSpecimens)C150 Specification for Portland CementC219 Terminology Relating to Hydraulic CementC595 Specification for Blended Hydraulic CementsC1157 Performance Specification for Hydraulic CementE456 Terminology Relating to Quality and Statistics3.Terminology3.1 DefinitionsFor definitions of terms relating to this testmethod,refer to Terminologies C219 and E456.4.Significance and Use4.1 This test method is designed to present in a standardizedformat information on the variability of strength of cementfrom a single source over a period of time.It can be applied toall hydraulic cements covered in Specifications C150,C595,and C1157.NOTE1It should be recognized that concrete strength variability isinfluenced by other factors in addition to cement strength variability.5.Sampling5.1 All sampling shall be performed by quality control ortesting personnel or someone specifically trained for thispurpose.5.2 Take random grab samples from delivery units or duringthe loading or unloading process.Delivery units larger than125 tons(115 Mg)shall be sampled during loading orunloading.If samples are taken during loading or unloading,the two or more portions that are to be composited to make asample shall be taken during the transfer to no more than 125tons(115 Mg)of cement.Identify samples by the date onwhich the cement they represent was shipped or received.NOTE2Standard statistical procedures are recommended for ensuringthat samples are selected by a random procedure.These procedures can beused to select the days within a month or within a week that samples willbe taken.Then the delivery unit or the time of day can be chosenrandomly.5.3 If taken from a truck or rail car,take at least twoseparate 5-lb(approximately 2.3-kg)grab samples and thor-oughly mix together to obtain a minimum 10-lb(4.5-kg)testsample.Sample only through hatches in the top of the unit.Remove approximately a 12-in.(300-mm)layer of cement.Make a hole before obtaining a sample to avoid collecting dustcollector material that may be discharged into the delivery unitafter the cement flow ceases.5.4 If taken from another point in the loading or unloadingprocess,the sample shall consist of a minimum of two separate5-lb(approximately 2.3-kg)grab samples thoroughly mixedtogether or at least 10 lb(4.5 kg)as accumulated by acontinuous sampler.Take care to avoid segregation and con-tamination of samples taken from screws,pneumatic systems,or air slides.1This test method is under the jurisdiction of ASTM Committee C01 on Cementand is the direct responsibility of Subcommittee C01.27 on Strength.Current edition approved April 1,2011.Published May 2011.Originallyapproved in 1979.Last previous edition approved in 2005 as C917 05.DOI:10.1520/C0917-05R11.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.5 When samples are taken at the cement plant andshipments or rate of production of the cement exceeds 25 000tons(23 000 Mg)per month,take samples at a rate of at leastten per month and at least two per week.When shipment or rateof production of the cement is less than 25 000 tons(23 000Mg)per month,take samples at a rate of at least one per 2500tons(2300 Mg).When samples are taken at the cement plant,in no instance shall samples be taken more frequently than oneper 200 tons(180 Mg)of cement shipped or received,exceptth