ASTM C917-98

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:C 917–98
Standard Test Method for
Evaluation of Cement Strength Uniformity From a Single
Source
This standard is issued under the fixed designation C 917; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope from a single source over a period of time. It can be applied to
all hydraulic cements covered in Specifications C150, C595,
1.1 This test method is intended for use in instances where
and C1157M.
thepurchaserdesiresinformationonthestrengthuniformityof
a hydraulic cement produced at a single source. It is intended
NOTE 1—It should be recognized that concrete strength variability is
that this method normally be used for the predominant cement influenced by other factors in addition to cement strength variability.
manufactured at a cement plant. Guidelines for sampling,
5. Sampling
testing, presentation of results, and evaluation are given.
1.2 Thevaluesstatedininch-poundunitsaretoberegarded 5.1 All sampling shall be performed by quality control or
testing personnel, or someone specifically trained for this
as the standard.
1.3 This standard does not purport to address all of the purpose.
5.2 Takerandomgrabsamplesfromdeliveryunitsorduring
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro- the loading or unloading process. Delivery units larger than
125 tons shall be sampled during loading or unloading. If
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use. samplesaretakenduringloadingorunloading,thetwoormore
portionswhicharetobecompositedtomakeasampleshallbe
2. Referenced Documents
taken during the transfer to no more than 125 tons of cement.
2.1 ASTM Standards: Identify samples by the date on which the cement they
C109/C109M Test Method for Compressive Strength of represent was shipped or received.
Hydraulic Cement Mortars (Using 2-in. or 50-mm Cube
NOTE 2—Standardstatisticalproceduresarerecommendedforensuring
Specimens)
thatsamplesareselectedbyarandomprocedure.Theseprocedurescanbe
C150 Specification for Portland Cement
used to select the days within a month or within a week that samples will
C219 Terminology Relating to Hydraulic Cement
be taken. Then the delivery unit or the time of day can be chosen
randomly.
C595M Specification for Blended Hydraulic Cements
C1157M Performance Specification for Blended Hydraulic
5.3 If taken from a truck or rail car, take at least two
Cement
separate 5-lb (approximately 2.3-kg) grab samples and thor-
E456 Terminology Relating to Quality and Statistics
oughly mix together to obtain a minimum 10-lb (4.5-kg) test
sample. Sample only through hatches in the top of the unit.
3. Terminology
Remove approximately a 12-in. (300-mm) layer of cement.
3.1 Definitions—Fordefinitionsoftermsrelatingtothistest
Makeaholebeforeobtainingasampletoavoidcollectingdust
method refer to Terminology C219 and Terminology E456.
collectormaterialthatmaybedischargedintothedeliveryunit
after the cement flow ceases.
4. Significance and Use
5.4 If taken from another point in the loading or unloading
4.1 Thistestmethodisdesignedtopresentinastandardized
process,thesampleshallconsistofaminimumoftwoseparate
format information on the variability of strength of cement
5-lb (approximately 2.3-kg) grab samples thoroughly mixed
together or at least 10 lb (4.5 kg) as accumulated by a
continuous sampler. Take care to avoid segregation and con-
tamination of samples taken from screws, pneumatic systems,
ThistestmethodisunderthejurisdictionofASTMCommitteeC01onCement
and is the direct responsibility of Subcommittee C01.27 on Strength.
or air slides.
Current edition approved July 10, 1998. Published December 1998. Originally
5.5 When samples are taken at the cement plant and
published as C917–79. Last previous edition C917–95a.
2 shipments or rate of production of the cement exceeds 25000
Annual Book of ASTM Standards, Vol 04.01.
Annual Book of ASTM Standards, Vol 14.02. tons (23000 Mg) per month, take samples at a rate of at least
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
C 917–98
tenpermonthandatleasttwoperweek.Whenshipmentorrate exceeds 5.5%, the data are of questionable precision, and
of production of the cement is less than 25000 tons (23000 laboratory procedures and equipment should be thoroughly
Mg) per month, take samples at a rate of at least one per 2500 examined.
tons (2300 Mg). When samples are taken at the cement plant,
6.2.3 Use the results of duplicate tests indicating acceptable
innoinstanceshallsamplesbetakenmorefrequentlythanone
precision to estimate the single-laboratory testing variation for
per 200 tons (180 Mg) of cement shipped or received, except
all other types of cement tested in that laboratory during the
thatsamplingofconsecutiveshipmentsispermittedwhenthey
same period of time, provided that duplicate tests have been
result from randomization.
made on at least one sample per month.
6. Procedure
7. Calculation
6.1 Test all samples for 7 and 28-day compressive strength
7.1 The calculations shall include the following:
in accordance with Test Method C109 using three specimens
7.1.1 Average Strength:
for each test age. To be comparable, all tests used in a single
X 1 X 1. 1 X
1 2 n
evaluation must be made in a single laboratory, and preferably
X 5 (1)
n
by the same laboratory operator.
6.1.1 Whenseparateevaluationsofasinglesourcearemade where:
X = average strength,
by two or more laboratories, additional tests of a standard
X,X ,.,X = strength of individual tests, each of
cement or exchange of portions of the same sample of cement 1 2 n
which is composed of the average of
may be necessary to determine differences in testing that are
three cubes in accordance with Test
likely to be obtained in the different laboratories. Five or more
Method C109, and
batches may be necessary to obtain a valid comparison
n = number of individual samples.
between laboratories. Statistical techniques must be used to
7.1.2 Total Standard Deviation:
assess the validity of differences that might be obtained.
Participation in the Cement Reference Sample Program of the
2 2 2
~X 2 X! 1~X 2 X! 1.1~X 2 X!
1 2 n
CCRL by both laboratories will be helpful in resolving S 5 (2)
Œ
t
~n 21!
differences that are found.
where:
6.1.2 When two laboratories exchange portions of the same
S = standard deviation, psi.
sample and prepare single batches, results from the two t
laboratoriesshallnotdifferbymorethan18.7%oftheaverage 7.1.3 Standard Deviation For Testing:
ofthetwolaboratories(seeTestMethodC109multilaboratory
S 50.862R
e
d2s). If a larger number of samples are exchanged the
differenceinaveragestrengthshallnotexceed18.7/ n %of
=
S = standard deviation estimated from tests of dupli-
the overall average strength, where n is the number of samples
e
cate batches mixed in a single laboratory,
exchanged and tested by each laboratory. A more precise
R = range, the difference between the strengths of the
calculation is outlined in Appendix X1.
duplicate batches from a single sample (all num-
6.2 Mix duplicate batches of mortar to determine the effect
bers are positive),
of testing variations on the uniformity of results made in a
R = average of the individual ranges, R, for the preced-
single laboratory. Make duplicate batches on a day different
ingtentestsofduplicatebatches.See6.2.1iffewer
from the original batch of mortar.
than ten ranges are available, and
6.2.1 When a uniformity testing program is started on
0.862 = range coefficient for duplicate tests of the same
shipments from a single source, make duplicate batches of
sample of cement.
mortar from every third cement sample. When duplicate tests
7.1.4 Coeffıcient of Variation for Testing:
have 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 variation V 5100 S /X
e e
for testing according to 7.1.3 and 7.1.4, respectively. Increase
where:
the number of duplicate batches used in the calculation until
V = coefficients of variation estimated from tests of dupli-
e
the results of ten cement samples are used in the calculation.
cate batches mixed in a single laboratory, and
Afterthattime,useonlythetenmostrecentresultsofduplicate
X = average of the strengths of the duplicate batches from
testing in the calculation of the standard deviation and coeffi-
which R is calculated.
cient of variation for testing. See Table 1.
7.1.5 Standard Deviation Corrected For Testing Variations:
6.2.2 When at least ten sets of duplicate batches have been
2 2
made and the coefficient of variation for testing is less than S 5 =S 2S (3)
c t e
4.0%, the frequency of testing duplicate batches may be
where:
reducedtooneoutoftenconsecutivecementsamples.Resume
S = net standard deviation of cement corrected for testing
c
testing one sample out of three if the coefficient of variation
error,
later exceeds 4.0%. If the coefficient of variation for testing
C 917–98
NOTE 3—Valuesforaveragesandstandarddeviationscanbecalculated
S = total standard deviations for all tests included in the
t
by other methods that are available in STP 15D. Electronic calculators
calculation, and
are available for obtaining these statistics directly.
S = standard deviation of duplicate tests run on split
e
sample to evaluate testing error.
The addition of the subscript 28 or 7 indicates the type of
Manual on Presentation of Data and Control Chart Analysis, ASTM STP 15 D,
strength data used in the calculation. ASTM 1976.
TABLE 1 Calculation of Standard Deviation for Testing
A
7-Day Data Average
B C D
Range R S
e
Sample
E
Date Test a Test b V Note
e
Number
psi (MPa) psi (MPa) psi (MPa) psi (MPa) psi (MPa) psi (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) 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. 5
02 /21 18 4700 (32.4) 4770 (32.8) 4735 (32.6) 70 (0.48) 102 (0.70) 88 (0.60) 1.89 % Av. 6
03 /04 21 4470 (30.8) 4610 (31.7) 4540 (31.3) 140 (0.96) 107 (0.73) 92 (0.64) 2.00 % Av. 7
03 /14 24 4030 (27.7) 3970 (27.3) 4000 (27.5) 60 (0.41) 101 (0.69) 87 (0.60) 1.92 % Av. 8
03 /19 27 4970 (34.2) 4820 (33.2) 4895 (33.7) 150 (1.03) 107 (0.73) 92 (0.63) 2.01 % Av. 9
03 /27 30 4550 (31.3) 4530 (31.2) 4540 (31.3) 20 (0.13) 96 (0.67) 84 (0.58) 1.84 % 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 10
05 /31 50 5030 (34.6) 4820 (33.2) 4925 (33.9) 210 (1.44) 121 (0.83) 104 (0.72) 2.27 % Av. last 10
06 /29 60 4830 (33.3) 4720 (32.5) 4775 (32.9) 110 (0.75) 112 (0.77) 97 (0.67) 2.10 % Av. last 10
07 /28 70 4400 (30.3) 4460 (30.7) 4430 (30.5) 60 (0.41) 107 (0.73) 92 (0.64) 2.00 % Av. last 10
08 /30 80 4550 (31.3) 4460 (30.7) 4505 (31.0) 90 (0.62) 108 (0.74) 93 (0.64) 2.02 % Av. last 10
09 /25 90 4930 (34.0) 5000 (34.4) 4965 (34.2) 70 (0.48) 108 (0.74) 93 (0.64) 2.01 % Av. last 10
10 /26 100 4950 (34.1) 4820 (33.2) 4885 (33.6) 130 (0.89) 107 (0.73) 92 (0.64) 1.97 % Av. last 10
11 /25 110 4670 (32.2) 4720 (32.5) 4695 (32.3) 50 (0.34) 106 (0.73) 91 (0.63) 1.93 % Av. last 10
12 /21 120 4450 (30.6) 4520 (31.1) 4485 (30.9) 70 (0.48) 96 (0.67) 84 (0.58) 1.80 % Av. last 10
28-Day Data
A B C D
Average Range R S
e
Sample
E
Date Test a Test b V Note
e
Number
psi (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) 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. 5
02 /21 18 5500 (37.9) 5530 (38.1) 5515 (38.0) 30 (0.20) 162 (1.11) 139 (0.96) 2.33 % Av. 6
03 /04 21 6320 (43.5) 6280 (43.3) 6300 (43.4) 40 (0.27) 144 (0.99) 124 (0.86) 2.06 % Av. 7
03 /14 24 5920 (40.8) 6010 (41.4) 5965 (41.1) 90 (0.62) 138 (0.94) 119 (0.82) 1.97 % Av. 8
03 /19 27 6300 (43.4) 6050 (41.7) 6175 (42.5) 250 (1.72) 150 (1.03) 129 (0.89) 2.14 % Av. 9
03 /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 10
05 /31 50 6670 (46.0) 6530 (45.0) 6600 (45.5) 140 (0.96) 118 (0.81) 102 (0.70) 1.68 % Av. last 10
06 /29 60 6350 (43.7) 6190 (42.6) 6270 (43.2) 160 (1.10) 127 (0.87) 109 (0.75) 1.80 % Av. last 10
07 /28 70 6500 (44.8) 6300 (43.4) 6400 (44.1) 200 (1.37) 126 (0.86) 109 (0.75) 1.78 % Av. last 10
08 /30 80 6200 (42.7) 6150 (42.4) 6175 (42.5) 50 (0.34) 113 (0.77) 97 (0.67) 1.58 % Av. last 10
09 /25 90 6630 (45.7) 6540 (45.1) 6585 (45.4) 90 (0.62) 119 (0.82) 103 (0.71) 1.63 % Av. last 10
10 /26 100 6230 (42.9) 6010 (41.4) 6120 (42.2) 220 (1.51) 137 (0.94) 118 (0.81) 1.88 % Av. last 10
11 /25 110 5920 (40.8) 6020 (41.5) 5970 (41.1) 100 (0.68) 138 (0.95) 119 (0.82) 1.90 % Av. last 10
12 /21 120 . . . . . . . . . . . . . .
Notes: Initially one out of three samples are tested in duplicate until at least ten duplicate test results are available.
A
Average of the test results a and b.
B
Absolute difference between tests a and b.
C
Average range is calculated for a minimum of 5 duplicate tests. Subsequently, ranges of the ten most recent duplicate tests are averaged.
D
Standard Deviation for testing is calculated as in 7.1.3: S = 0.862 3 R .
e
E
Coefficient of Variation for testing is calculated as in 7.1.4: V = 100 S / X . Note that X is the average strength of the duplicate batches from which R is determined.
e e
8. Report 8.1.5 Period of time represented by the report.
8.2 For ongoing programs the minimum period covered by
8.1 Sufficient information shall be provided to identify the
cement sampled including: the report shall include all strength tests made in the preceding
8.1.1 Name of manufacturer and location, three months, but in no instance less than tha
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