ASTM C917-2005(2011) Standard Test Method for Evaluation of Cement Strength Uniformity From a Single Source《同一货源水泥强度均匀性评定的标准试验方法》.pdf

1、Designation: C917 05 (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, th

2、e 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

3、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 unit

4、s 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

5、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 Hydraul

6、ic 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

7、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.NOTE 1It should be recognized that concrete

8、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

9、 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 ceme

10、nt. Identify samples by the date onwhich the cement they represent was shipped or received.NOTE 2Standard 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 wi

11、llbe 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

12、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 sh

13、all 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.5.5 When samples

14、 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 0001This test method is un

15、der the jurisdiction ofASTM 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 AS

16、TM 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshoh

17、ocken, PA 19428-2959, United States.Mg) 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, exceptthat sampling of conse

18、cutive shipments is permitted when theyresult from randomization.6. Procedure6.1 Test all samples for 7- and 28-day compressive strengthin accordance with Test Method C109/C109M using threespecimens for each test age. To be comparable, all tests used ina single evaluation must be made in a single la

19、boratory andpreferably by the same laboratory operator.NOTE 3When separate evaluations of a single source are made by twoor more laboratories, additional tests of a standard cement or exchange ofportions of the same sample of cement may be necessary to determinedifferences in testing that are likely

20、 to be obtained in the differentlaboratories. Five or more batches may be necessary to obtain a validcomparison between laboratories. Statistical techniques must be used toassess the validity of differences that might be obtained. Participation inthe Cement Proficiency Sample Program of the CCRL by

21、both laborato-ries will be helpful in resolving differences that are found.6.1.1 When two laboratories exchange portions of the samesample and prepare single batches, results from the twolaboratories shall not differ by more than 18.7 % of the averageof the two laboratories (see Test Method C109/C10

22、9M multi-laboratory d2s). If a larger number of samples are exchangedthe difference in average strength shall not exceed 18.7/=n% of the overall average strength, where n is the number ofsamples exchanged and tested by each laboratory. A moreprecise calculation is outlined in Appendix X1.6.2 Mix dup

23、licate batches of mortar to determine the effectof testing variations on the uniformity of results made in asingle laboratory. Make duplicate batches on a day differentfrom the original batch of mortar.6.2.1 When a uniformity testing program is started onshipments from a single source, make duplicat

24、e batches ofmortar from every third cement sample. When duplicate testshave been made from a minimum of five cement samples,calculate the average range, R , for the available duplicates,then calculate standard deviation and coefficient of variationfor testing according to 7.1.3 and 7.1.4, respective

25、ly. Increasethe number of duplicate batches used in the calculation untilthe results of ten cement samples are used in the calculation.After that time, use only the ten most recent results of duplicatetesting in the calculation of the standard deviation and coeffi-cient of variation for testing. See

26、 Table 1.6.2.2 When at least ten sets of duplicate batches have beenmade and the coefficient of variation for testing is less than4.0 %, the frequency of testing duplicate batches can bereduced to one out of ten consecutive cement samples. Resumetesting one sample out of three if the coefficient of

27、variationlater exceeds 4.0 %. If the coefficient of variation for testingexceeds 5.5 %, the data are of questionable precision, andlaboratory procedures and equipment should be thoroughlyexamined.6.2.3 Use the results of duplicate tests indicating acceptableprecision to estimate the single-laborator

28、y testing variation forall other types of cement tested in that laboratory during thesame period of time, provided that duplicate tests have beenmade on at least one sample per month.7. Calculation7.1 The calculations shall include the following:7.1.1 Average Strength:X 5X11 X21 .1 Xnn(1)where:X = a

29、verage strength,X1,X2,.,Xn= strength of individual tests, each ofwhich is composed of the average ofcubes in accordance with Test MethodC109/C109M, andn = number of individual samples.7.1.2 Total Standard Deviation:St5X12 X!21X22 X!21 .1Xn2 X!2n 2 1!(2)where:St= standard deviation, psi.7.1.3 Standar

30、d Deviation For Testing:Se5 0.862RSe= standard deviation estimated from tests of dupli-cate batches mixed in a single laboratory,R = range, the difference between the strengths of theduplicate batches from a single sample (all num-bers are positive),R = average of the individual ranges, R, for the p

31、reced-ing ten tests of duplicate batches. See 6.2.1 if fewerthan ten ranges are available, and0.862 = range coefficient for duplicate tests of the samesample of cement.7.1.4 Coeffcient of Variation for Testing:Ve5 100 Se/Xwhere:Ve= coefficients of variation estimated from tests of dupli-cate batches

32、 mixed in a single laboratory, andX = average of the strengths of the duplicate batches fromwhich R is calculated.7.1.5 Standard Deviation Corrected For Testing Variations:Sc5 =St22 Se2(3)where:Sc= net standard deviation of cement corrected for testingerror,St= total standard deviations for all test

33、s included in thecalculation, andSe= standard deviation of duplicate tests run on splitsample to evaluate testing error.The addition of the subscript 28 or 7 indicates the type ofstrength data used in the calculation.C917 05 (2011)2NOTE 4Values for averages and standard deviations can be calculatedb

34、y other methods that are available in ASTM STP 15 D.3Electroniccalculators are available for obtaining these statistics directly.TABLE 1 Calculation of Standard Deviation for TestingDateSampleNumber7-Day Data AverageARangeBRCSeDVeENoteTest A Test Bpsi (MPa) psi (MPa) psi (MPa) psi (MPa) psi (MPa) ps

35、i (MPa)01 /06 3 4900 (33.7) 4960 (34.2) 4930 (34.0) 60 (0.41) . . . . . . . . . . . . . . . . . .01 /16 6 4580 (31.5) 4670 (32.2) 4625 (31.8) 90 (0.62) . . . . . . . . . . . . . . . . . .01 /30 9 4650 (32.0) 4850 (33.4) 4750 (32.7) 200 (1.37) . . . . . . . . . . . . . . . . . .02 /05 12 4400 (30.3)

36、4510 (31.1) 4455 (30.7) 110 (0.75) . . . . . . . . . . . . . . . . . .02 /13 15 4380 (30.2) 4300 (29.6) 4340 (29.9) 80 (0.55) 108 (0.74) 93 (0.64) 2.02 % Av. 502 /21 18 4700 (32.4) 4770 (32.8) 4735 (32.6) 70 (0.48) 102 (0.70) 88 (0.60) 1.89 % Av. 603 /04 21 4470 (30.8) 4610 (31.7) 4540 (31.3) 140 (0

37、.96) 107 (0.73) 92 (0.64) 2.00 % Av. 703 /14 24 4030 (27.7) 3970 (27.3) 4000 (27.5) 60 (0.41) 101 (0.69) 87 (0.60) 1.92 % Av. 803 /19 27 4970 (34.2) 4820 (33.2) 4895 (33.7) 150 (1.03) 107 (0.73) 92 (0.63) 2.01 % Av. 903 /27 30 4550 (31.3) 4530 (31.2) 4540 (31.3) 20 (0.13) 96 (0.67) 84 (0.58) 1.84 %

38、Av. 10 (6)04 /30 40 4750 (32.7) 4920 (33.9) 4835 (33.3) 170 (1.17) 109 (0.75) 94 (0.65) 2.06 % Av. last 1005 /31 50 5030 (34.6) 4820 (33.2) 4925 (33.9) 210 (1.44) 121 (0.83) 104 (0.72) 2.27 % Av. last 1006 /29 60 4830 (33.3) 4720 (32.5) 4775 (32.9) 110 (0.75) 112 (0.77) 97 (0.67) 2.10 % Av. last 100

39、7 /28 70 4400 (30.3) 4460 (30.7) 4430 (30.5) 60 (0.41) 107 (0.73) 92 (0.64) 2.00 % Av. last 1008 /30 80 4550 (31.3) 4460 (30.7) 4505 (31.0) 90 (0.62) 108 (0.74) 93 (0.64) 2.02 % Av. last 1009 /25 90 4930 (34.0) 5000 (34.4) 4965 (34.2) 70 (0.48) 108 (0.74) 93 (0.64) 2.01 % Av. last 1010 /26 100 4950

40、(34.1) 4820 (33.2) 4885 (33.6) 130 (0.89) 107 (0.73) 92 (0.64) 1.97 % Av. last 1011 /25 110 4670 (32.2) 4720 (32.5) 4695 (32.3) 50 (0.34) 106 (0.73) 91 (0.63) 1.93 % Av. last 1012 /21 120 4450 (30.6) 4520 (31.1) 4485 (30.9) 70 (0.48) 96 (0.67) 84 (0.58) 1.80 % Av. last 10DateSampleNumber28-Day DataA

41、verageARangeBRCSeDVeENoteTest A Test Bpsi (MPa) psi (MPa) psi (MPa) psi (MPa) psi (MPa) psi (MPa)01 /06 3 6370 (43.9) 6620 (45.6) 6495 (44.7) 250 (1.72) . . . . . . . . . . . . . . . . . .01 /16 6 6250 (43.1) 6020 (41.5) 6135 (42.3) 230 (1.58) . . . . . . . . . . . . . . . . . .01 /30 9 6050 (41.7)

42、6120 (42.2) 6085 (41.9) 70 (0.48) . . . . . . . . . . . . . . . . . .02 /05 12 6020 (41.5) 6230 (42.9) 6125 (42.2) 210 (1.44) . . . . . . . . . . . . . . . . . .02 /13 15 5600 (38.6) 5420 (37.3) 5510 (38.0) 180 (1.24) 188 (1.29) 162 (1.12) 2.67 % Av. 502 /21 18 5500 (37.9) 5530 (38.1) 5515 (38.0) 30

43、 (0.20) 162 (1.11) 139 (0.96) 2.33 % Av. 603 /04 21 6320 (43.5) 6280 (43.3) 6300 (43.4) 40 (0.27) 144 (0.99) 124 (0.86) 2.06 % Av. 703 /14 24 5920 (40.8) 6010 (41.4) 5965 (41.1) 90 (0.62) 138 (0.94) 119 (0.82) 1.97 % Av. 803 /19 27 6300 (43.4) 6050 (41.7) 6175 (42.5) 250 (1.72) 150 (1.03) 129 (0.89)

44、 2.14 % Av. 903 /27 30 6350 (43.7) 6410 (44.2) 6380 (44.0) 60 (0.41) 141 (0.97) 122 (0.84) 2.00 % Av. 10 (6)04 /30 40 6050 (41.7) 5940 (40.9) 5995 (41.3) 110 (0.75) 127 (0.87) 109 (0.75) 1.82 % Av. last 1005 /31 50 6670 (46.0) 6530 (45.0) 6600 (45.5) 140 (0.96) 118 (0.81) 102 (0.70) 1.68 % Av. last

45、1006 /29 60 6350 (43.7) 6190 (42.6) 6270 (43.2) 160 (1.10) 127 (0.87) 109 (0.75) 1.80 % Av. last 1007 /28 70 6500 (44.8) 6300 (43.4) 6400 (44.1) 200 (1.37) 126 (0.86) 109 (0.75) 1.78 % Av. last 1008 /30 80 6200 (42.7) 6150 (42.4) 6175 (42.5) 50 (0.34) 113 (0.77) 97 (0.67) 1.58 % Av. last 1009 /25 90

46、 6630 (45.7) 6540 (45.1) 6585 (45.4) 90 (0.62) 119 (0.82) 103 (0.71) 1.63 % Av. last 1010 /26 100 6230 (42.9) 6010 (41.4) 6120 (42.2) 220 (1.51) 137 (0.94) 118 (0.81) 1.88 % Av. last 1011 /25 110 5920 (40.8) 6020 (41.5) 5970 (41.1) 100 (0.68) 138 (0.95) 119 (0.82) 1.90 % Av. last 1012/21 120 . . . .

47、 . . . . . . . . . .Notes: Initially one out of three samples are tested in duplicate until at least ten duplicate test results are available.AAverage of the test results A and B.BAbsolute difference between tests A and B.CAverage range is calculated for a minimum of five duplicate tests. Subsequent

48、ly, ranges of the ten most recent duplicate tests are averaged.DStandard deviation for testing is calculated as in 7.1.3: Se= 0.862 3 R .ECoefficient of variation for testing is calculated as in 7.1.4: Ve= 100 Se/ X . Note that X is the average strength of the duplicate batches from which R is deter

49、mined.8. Report8.1 Sufficient information shall be provided to identify thecement sampled including:8.1.1 Name of manufacturer and location,8.1.2 Type of cement or other identification,8.1.3 Location of sampling,8.1.4 Laboratory designation, and8.1.5 Period of time represented by the report.8.2 For ongoing programs, the minimum period covered bythe report shall include all strength tests made in the precedingthree months, but in no instance less than that period of timenecessary to include 28-day strength tests of 20 consecutivesamples.3Manual on Presentation of Data an