SHRP-P-636 Portland Cement Concrete Core Proficiency Sample Program G.W. Steele Steele Engineering, Inc. Tornado, West Virginia Strategic Highway Research Program National Research Council Washington, DC 1993 SHRP-P-636 Contract P-001 Program Manager: Neil Hawks Project Manager: Cheryl Richter Production Editor: Elizabeth Lucks Program Area Secretary: Cindy Baker May 1993 key words: compressive strength core sample laboratory accreditation poisson s ratio portland cement concrete static modulus tensile strength Strategic Highway Research Program National Academy of Sciences 2101 Constitution Avenue N.W. Washington, DC 20418 (202) 334-3774 The publication of this report does not necessarily indicate approval or endorsement of the fmdings, opinions, conclusions, or recommendations either inferred or specifically expressed herein by the National Academy of Sciences, the United States Government, or the American Association of State Highway and Transportation Officials or its member states. © 1993 National 350/NAP/593 Academy of Sciences • Acknowledgments The research described herein was supported by the Strategic Highway Research Program (SHRP). SHRP is a unit of the National Research Council that was authorized by section 128 of the Surface Transportation and Uniform Relocation Assistance Act of 1987. iii Contents Summary of Research ............................................... 1 Appendix I, Correspondence dated 11/2/89 from Iowa describing concrete mixes .......................................... 3 Appendix II, Correspondence dated 11/8/89 from Iowa to all participating laboratories ....................................... 6 Appendix III, Preliminary report dated 2/90 from Iowa concerning results of PCC core testin ................................. 14 Appendix IV, Correspondence dated 2/27/90 to statistician concerning analysis of test data ............................. 23 Appendix V, Correspondence dated 10/5/90 to statistician concerning analysis of test data ............................. 25 Appendix VI, Memorandum data 12/21/90 from statistician on variance component analysis (contains matrix of all test data) ..................................... 28 Appendix VII, Memorandum dated 3/19/91 from statistician on precision statements ................................... 52 Appendix VIII, Documents relating to the authorization of SHRP laboratory to proceed with testing of LTPP cores .................. 57 Appendix IX, AASHTO/ASTM format precision statements .................... 60 v - Abstract This document provides a description Proficiency Sample Program. and process of the Portland Cement Concrete Core vii Executive Summary One element of Quality Assurance (QA) for laboratory testing that was deemed to be of key importance by SHRP, as a result of Expert Task Group (ETG) recommendations, is the American Association of State Highway and Transportation Officials (AASHTO) accreditation program (AAP) for laboratories. All laboratories providing long-term pavement performance (LTPP) testing services were required to be accredited by AAP. Most of the laboratory tests on LTPP field samples were addressed by the AAP, which includes on-site inspections of equipment and procedures, and participation in applicable proficiency sample series. However, a few critical tests in the SHRP LTPP studies were not fully addressed. After extensive consultation and careful study, it was determined that supplemental programs should be designed to provide assurance that quality test data would be obtained by using approaches similar to those provided by AAP for other tests. One supplemental program approved for implementation was the Portland Cement Concrete (PCC) Core Proficiency Sample Program. The program was designed to provide precision data concerning the static modulus of elasticity, poisson's ratio, splitting tensile strength, and compressive strength. The PCC core program was modeled after the familiar Cement and Concrete Reference laboratory (CCRL) proficiency sample programs at the National Institute of Standards and Technology (NIST). The core samples were prepared and distributed to participants, the raw test data was collected and entered into a matrix for analysis, and an interim report to participants was distributed for SHRP by the Iowa Department of Transportation's Office of Materials. Two different PCC mixes were prepared by the Iowa Materials Laboratory and cast into forms that would allow 4 in. diameter by approximately 9 in. length cores to be obtained for testing. All cores were taken, cured and shipped in accordance with standard practice. Twelve cores were sent to each participating laboratory for testing at age 56 days, six from each mix. Instructions to the laboratories directed that two cores from each mix be tested in compression, two from each mix be tested for splitting tensile strength, and two be tested for static modulus of elasticity and poisson's ratio. A single operator was to perform the same test on both samples. Different operators could be used for different tests. Explicit directions were included concerning procedures to be followed for each test. Raw test data were returned to Iowa for matrix entry and preliminary reports to participants. Subsequently, preliminary scatter dia:zrams an5 individualized tables of results were distributed to the cooperating laborat_:_ries. A 3 1_ in. floppy disk containing the raw test data along with the core sample identification key was prepared by the Iowa Materials Office and forwarded to the SHRP Quality Assurance Engineer when all data had been received. The floppy disk was then transmitted to the SHRP Statistician for final analysis and determination of test precision. The statistician's initial report indicated that potential outliers existed in the data which should be investigated. An investigation was conducted by the Quality Assurance Engineer. It was determined that the outliers should be set aside in the final analysis. The SHRP authorization to proceed with tests of LTPP field samples was issued based on results of the proficiency sample tests. Precision statements were derived and drafted in the standard AASHTO/ASTM format for use by standards writing committees as they deem appropriate. Appendices to this report contain the complete set of supporting documents for this program as listed in the table of contents. Thirteen (13) laboratories participated in this program. Each participant has made a substantial contribution to the successful completion of SHRP research in the LTPP program. Participants were: Florida Department of Transportation, Gainesville, Florida Iowa Department of Transportation, Ames, Iowa Federal Highway Administration, Denver, Colorado California Department of Transportation, Sacramento, California West Virginia Department of Transportation, Charleston, West Virginia Law Engineering, Atlanta, Georgia National Aggregates Association/National Ready Mix Concrete Association, Silver Spring, Maryland Bureau of Reclamation, Denver, Colorado Waterways Experiment Station, Vicksburg, Mississippi Concrete Materials and Technical Services, Skokie, Illinois CANMET, Ottawa, Ontario, Canada Wiss, Janey and Eisner, Northbrook, Illinois New York Department of Transportation, Albany, New York APPENDIXI ,,9 l , ," _. Form 000032 3-86 H-8687 IOWADEPARTMENTOFTRANSPORTATION 800 Lincoln Way, Am, es, Iowa 50010 515/239-1649 Ref. No. 435.24 November 2, 1989 Garland W. Steele President,Steie Engineering,Inc. Box 173 Tornado, West Virginia 25Z02 Dear Garland: Attached is informationon the "Precisionand Accuracy Determinationfor P.C. Concrete Core Testing'. The concrete Iowa's 6-4 mix is c_monly used for low traffic county roads. The mix on is October used on19 primary and on interstate paving. was C-4 poured and cored October 26 and 27. forwill yourbe review in you the next reek two. Please lettesting" me know We sending a draft ofor "instructionsfor if you have any questions about our plans. Sincerely, Cement & Concrete Kevin Jones Engineer C_ KJ:sh Attach. co: B. Brown 4 L_ '_ v _-_-v-I" MLR-89-11 Concrete Pour October 19, 1989 8:00 a.m. Special InvestigationsLab Materials Cement - NorthwesternType I Coarse Aggregate- Martin Marietta Ferguson Fine Aggregate- Halletts Materials,Ames Air EntrainingAgent - Protex AES Mix No. B-4 C-4 Cement Ibs. Coarse Agg. Ibs. Fine Agg. Ibs. 492 1558 1558 5.33 624 1499 1495 5.75 Test Results Mix No. W/C Slump Air B-4 .60 2.0" 4.8% C-4 .49 1.5" 4.9% ? Air Entraining Agent Oz. APPENDIX II • o J ° • Materials Office lowa Department of Transportation Cement and Concrete Laboratory 800 Lincoln Way Ames, Iowa 50010 (515) 239-1649 Sponsored by Strategic Highway Research Program (SHRP) November TO: 8, 1989 Participating SUBJECT: P.C.C. Laboratories Core Samples for Testing The samples for precision and accuracy determination for P.C.C. core testing are being shipped to you the week of November 27th. Shipment will consist of two boxes each containing six p.c.c. cores. The samples are packaged in plastic bags to retain the moisture and are identified as No. 1 and No. 2. The core samples upon arrival should be cured in lime water as per ASTM C-192 until the test date of December 14, 1989. If you do not receive the samples or if the samples you receive are seriously damaged, notify us immediately and the necessary replacement will be sent. The tests should be conducted on December 14 if possible and the test results sent to me. After receiving the test results from each participating laboratory, the results will be sent to AMRL for analysis. The results of the AMRL analysis will be sent to each participating laboratory. Instructions for testing and the necessary sheets for reporting the test results are enclosed. Please read these instructions carefully before proceeding with the tests. 7 Sincerely, Kevin B. Jones Cement & Concrete Engineer Materials Office Iowa Department of Transportation Enclosures I IOWA DEPARTMENT OF TRANSPORTATION P.C.C. Core Samples for Testing A total of twelve P.C.C. Core samples will be sent to each participating laboratory. Six cores will be from each mix. Two concrete cores from each mix will be tested by each participating laboratory for (a} compressive strength, (b} splitting tensile strength and (c} static modulus of elasticity. It is recommended that one operator make the same test on both samples APPLICABLE DOCUMENTS AASHTO T22-88I Compressive Specimens AASHTO T24-86 Obtaining and Testing Beams of Concrete AASHTO T198-88I Splitting Tensile Strength Concrete Specimens AASHTO T67-85 Load Verification AASHTO T231-87I Capping ASTM C469-87 Strength of Cylindrical Drilled and Sawed of Cylindrical of Testing Cylindrical Cores Concrete Concrete Machine Specimens Test Method for Static Modulus of Elasticity and Poisson's Ratio of Concrete in Compression INSTRUCTIONS - COMPRESSIVE STRENGTH TESTING This test shall be conducted following modifications: - as per AASHTO T22-881 except for the - The diameter (D} of the test specimen shall be determined to the nearest 0.01 inch by averaging two diameters measured by a caliper at right angles to each other at about the midheight of the specimen. - Measure the length of specimen before capping (LO) and after capping (L) to the nearest 0.1 inch prior to testing. The length shall be determined by averaging four measurements equally spaced around the specimen. The length of the specimen when capped, shall be as nearly as practicable twice its diameter. Section 6.2 of AASHTO T24-86 for specimen end preparation shall be followed. - Test specimens shall be sawed on both the top and bottom ends of the core to achieve the desired L/D ratio of approximately 2.00. (Use the length of the capped specimen to compute the L/D ratio}. - - AASHTO T231-87I procedure for capping hardened concrete specimens shall be followed for capping both ends of specimen. Neither end of test specimens when tested shall depart from perpendicularity to the axis by more than 0,5 o (equivalent to 1/8 inch in 12 inches). - Type of fracture AASHTO T22-88I). - SPLITTING should be reported TENSILE STRENGTH (Refer to Fig. 2 of TESTING - This test shall be carried out in accordance except for the following modifications: with AASHTO T198-88I - Measure the diameter (D) and the length (L) of the test specimens to the nearest 0.01 inch following section 5.2 of AASHTO T198-88I. - The test specimen shall be sawed or ground to achieve a uniform length, and the end surfaces shall conform to section 6.2 of AASHTO T24-86. The L/D ratio shall be nearly as possible to 2. Test specimens shall be trimmed as not to exceed 1-1/4 inch at the bottom of the specimen and up to 1 inch at the top of the specimen. (The finished ends are not to be capped_. - Type of fracture AASHTO T22-88I). - STATIC MODULUS should be reported OF ELASTICITY (Refer to Fig. 2 of TESTING This test shall be performed in accordance except for the following modifications: with ASTM C469-87 - The diameter (D) and the length (L) of the test specimen shall be determined in the same manner as described for compressive strength testing. - L/D ratio of the specimen shall be determined in the same manner as described for compressive strength testing. - Ends of the test specimen 87I. - The test specimen shall be weighed prior to testing and the weight recorded to the nearest gram. The unit weight (CW) shall be calculated to the nearest 1 pcf by dividing the weight of the specimen by its volume using the dimensions determined above. - Deformation should be measured by a linear variable differential transformer (LVDT). • shall be capped as per AASHTO T231- - The value of elasticity testing shall correspond to S _0._orof the the modulus ultimateof load determined in the compressive strength testing. - Calculate the modulus of elasticity to the nearest 50,000 and poisson's ratio to the nearest 0.01. - REPORTING - The test results shall be reported on the attached forms and returned to the Iowa Department of Transportation as soon as possible. /0 psi _J E E o ¢.J QJ 4-- S..i.a ,,,.v" _,J U I.i.. 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IOWA DEPARTMENT OF TRANSPORTATION HIGHWAY DIVISION OFFICE OF MATERIALS AMES, IOWA 50010 (515) 2,59-1649 /5 Summary of Results - General In most cases, averages, standard deviations, and coefficients of variation are given with all results reported, and then with one or more outlying results omitted. In some cases two or more recalculations, with laboratories omitted, have been done for the same test; and in these cases, all of the laboratories omitted in previous recalculations are also omitted in subsequent ones. Results omitted are values which are more than three standard deviations from the mean of one or both samples. In most cases, elimination of these outlying results has little effect on the average, but may have a more pronounced effect on the standard deviation and coefficient of variation. Scatter A set of scatter diagrams Diagrams is supplied with the report. The manner of preparing scatter diagrams, and their interpretation, is described in the Crandall and Blaine paper, published in the 1959 ASTM Proceedings. Each of the laboratories will receive a complete set of diagrams. In those instances where the laboratory was unable to report results, diagrams will still be furnished. A scatter diagram is plotted for each test method by taking the results received from each laboratory and plotting the value for the odd numbered samples on the X, or horizontal axis, against the value for the even numbered samples on the Y, or vertical axis. To locate your point, just plot as you would when plotting any scatter diagram. The vertical and horizontal lines of dashes, which divide the diagrams into samples respectively. The first line of print under the diagram includes the test number, as given on the data sheet, the test title, and the number of data points on the diagrams. The number of plotted points may not agree with the total number of data pairs included in the analysis because a few points may be off the diagram, and some points may represent several data pairs, which are identical. Laboratories whose points are off the diagram will have a rating of + 1 for that particular test. As described in Crandall and Blaine, a tight circular pattern of points around the intersection of the median lines is the ideal situation. A stretching out of the pattern into the first (upper right} and third (lower left) quadrants indicates some kind of bias or tendency for laboratories to get high or low results on both samples. Examination of the scatter diagrams indicates strong evidence of bias on almost all tests. /6 , Each laboratory receives an individualized Table of Results. The Table of Results shows the test number, test title and the reporting unit in the first three columns. Thereafter, it lists in order, the laboratory's results for the odd and even numbered samples, overall averages for the odd and even numbered samples and the laboratory's ratings for the odd and even samples. (See reverse for an explanation of the scatter diagrams.} The laboratory ratings, shown in the Table of Results for the individual laboratory, were determined in the manner described by Crandall and Blaine, using a rating scale of 1 to 5 instead of 0 to 4. The ratings nave no valid standing beyond indicating the difference between the individual laboratory result and the average for a particular test. The table which follows, details ratings and the averages. Ratings 5 4 3 2 1 the relationship Range (Number of Standard Deviations} Less than i i to 1.5 1.5 to 2 2 to 2.5 Greater than 2.5 between the Number (Per 1000 of Laboratories) that might have greater variation 317 134 45 12 -- The sign of the rating merely indicates whether the result reported was greated or less than the average obtained. In cases where some of the laboratories' results are eliminated, averages, standard deviations, coefficients of variation, and the ratings of the other laboratories' results, are recalculated, using the data remaining after the elimination. • t _ q _ Lo • ,--i oo • • N /g COMPRESSIVE STRENGTH RESULTS CONCRETE SAMPLE NOS.1 & 2 i 1000 _ ; 6,800" O iO : ="6,600• O o i o o q,D in, 0 • ............................ 0 ..O ..........................................o..-._ U: _ 6,400. a2 : X " °6,200. i _5, i •_I' '8001 ' I ' 4600 TESTNO. 1 ' I " i , I ' ' ' I' ' ' _ " ' I ' ' ' I i 4800 5000 5200 5400 5600 5800 SAMPLE NO.I : COMP. STR-56D PSI COMPSTR-56D SAMPLENO. 1 AVO 5390.8 , 6000 13 POINTS S.D. 265.2 C.V. 4..92 SAMPLENO. 2 AVG 64.66.2 S.D. 270.3 , C.V. 4..18 SPLITTING TENSILE STRENGTH RESULTS CONCRETE SAMPLE NOS.1 &:2 00 ' : 0 7_' _7_, i ! : 6_- !o :0 _6_, o o :o 0 ! o • eeeeoeeeeeee_eooeeeooeeeeeeeoeee_egeele_oeeae_ooeoeJeoeooee 0 5_. . ooe_eoeeoe • o • eee • .et eee • :: z i 4_. o i. o ,,,, 300 i,,,, 350 i i,,,, 400 i,,,, 4_ i, ,i, 500 I,,,', 5_ I,,,' 6_ I'' 6_ '' 7_ SkMPLE NO.1: _NSILE Sm-_D _1 TEST NO. 2 TENSILESTR-56D 12 POINTS SAMPLE NO. 1 AVG 521.2 S.D. 63.3 C.V. 12.15 SAMPLE NO. 2 AVG 589.5 S.D. 91.7 C.V. 15.55 2.0 STATIC MODULUS RESULTS CONCRETE SAMPLE NOS.1 & 2 . 5.50 0 O O gSO0. _ :: • '_ X : :. ,_ 4.50" ........... o.. U"a • Go eo o 0 0 i • •oQ Qao•. 8 _i . •... • .. egeeloeeoeQuJ • • QeeeeOOOlO•OOQe •QOneQQD..ee** _J 4.00.. Oql, • c,_ 0 _ 0 : • _. 3.50' a. 300 .... 3.00 ' I " ' " ' I " "' ' ' I ' " ' " I ' ' " 3.50 4.00 4.50 5.00 SAMPLE NO.I : MODULUS-58D 151X 1,000,000 TESTNO.3 STATICMOD-56D SAMPLE NO. 1 AVG 4.145 S.D. 0.459 5.50 10 POINTS C.V. 11.08 SAMPLE NO.2 AVG 4.400 S.D. 0.402 C.V. 9.15 2./ " POISSON'S RATIO RESULTS •CONCRETE SAMPLE NOS.I& 2 0.260- o O 0.240- o O ='=0.220- o Z O ¢/'} i.,.eee..ooeo,oo,e,.,,e,.,..eo...o.ool,e, oo.t. o,q-.eo.o..,eoot'o. '''''''eoo=eo''°''" 5 0.200Oo ,5 0.180. o _J ..,I Q. _ 0.160" o 0.140. C, 0.120 . , • , . , ' , ' , ' , ' , 0.120 0.1400.1600.180 0.200 0.220 0.2400.260 SAMPLE NO.I:POISSON'S RATIO TESTNO. 4. POISSON'SRATIO-56D 7 POINTS SAMPLENO. 1 AVG 0.207 S.D. 0.039 C.V. 18.74 SAMPLENO. 2 AVG 0.206 S.D. 0.04.6 C.V. 22.33 ,ZZ. APPENDIX IV February 27, 1990 Robin High TRDF 2602 Dellana Lane Austin, TX 78746 Dear Robin: Subject: SHRP Portland Program. Cement Concrete Core Proficiency Sample Enclosed is a floppy disk with the raw data gathered from the subject program. Three pairs of cores for each of two mixes were distributed to participating laboratories. One pair from each mix was to be tested in compression, one in split tension, and one pair in static modulus including poisson's ratio. Replicate sets of values for each of the four properties for each mix were obtained. However, all values were not determined by all laboratories. Therefore, the degrees of freedom available differs for each of the properties to be evaluated. Please review the data and I will be in contact with concerning the analyses you feel would be most appropriate. sure that Virgil could provide some valuable guidance also. Yours very truly Garland W. President, Steele, Steele P.E. Engineering, enclosure: floppy disk Box 173 • Tornado, West Virginia Inc. 25202 • Tele (304) 727-8719 you I am APPENDIXV Z,E' October Robin TRDF 2602 1990 High Dellana Austin, Dear 5, TX Lane 78746 Robin: Subject: SHRP Portland Program. Cement Concrete Core Proficiency Sample The report, dated 5/21/90, on components of variance analysis of data gathered in the subject program has been carefully reviewed. As suggested on page 4, the two possible outlier values in compressive strength data have been investigated. Both the laboratories involved in the performance of the tests and the laboratory responsible for preparation of the samples were queried concerning possible assignable causes that may have affected the two values. The final conclusions are based on the recollections and comments of the participating parties. Each felt that the values were the result of an assignable cause, however there was not agreement (and there was no objective information) that would lead to the positive identification of same. The first possible outlier (page 2, figure 2) in the compressive strength data was likely the result of misidentification of a specimen or cross-identification of two specimens. The second possible outlier in the compressive strength data was likely the result of an error in recording the dial reading or mis-identification of specimens. Based upon the above, it is recommended that the data be retained and placed in the SHRP data bank. However, the two values in question should be identified in the data bank as probable outliers, and the components of variance analysis placed in the data bank and used by SHRP should exclude these two values. The suggestions on page I0 of the report concerning tensile strength values were of greater concern, since it was felt that their implementation would be quite time consuming and relatively costly. Careful review of the presentation of data in the report then revealed that replicate columns 2 and 3 under tensile strength in figure 2 on page 2 have been transposed. Investigation of the original worksheets verifies that column 2 data should be moved to column 3 and column 3 data should be moved to results. a problem strength). specimens column 2. This will substantially change the end It should be noted that lab I will likely still present (ie reporting mix 1 strength greater than mix 2 However, the possible cross-identification of noted previously would involve one or more of these cores. Box 173.Tomado, Z_ WcstVirgmia 25202-Tclc.(304)727-8719 The aforementioned review transposition of values and Poisson's ratio should be interchanged It is glitch also probable that these when the data was transpositions transferred Please call after completion of strength, modulus, and Poisson's determine the appropriate course of obtained therefrom. Let Yours me know very Garland W. President, cc: Adrian if you have any questions truly Steele, Steele Pelzner revealed that the same has ocurred for the modulus of elasticity in figure 2 on page 2. Columns 2 and in each case. P.E. Engineering, Inc. resulted from a from one system to the ration action 3 computer another. analysis for tensile at which time we can based upon the results concerning the above items. ..,. .. TRD . TECH MEMO: AU-127 AUTHORS: Robin High'l_ DISTRIBUTION: Garland SUBJECT: Variance Component Concrete Core Proficiency A proficiency variance cement engineering modulus Steele, cores. material determined by the indirect compression data and test. Poisson's analysis proficiency observed between phase program various were laboratory an strength, testing tensile for two mixes The tensile estimated strength, (medium compressive and high strength strength, from an test program was modulus unconfined as well as the in Figure i. cement analysis It.will properties the of four Portland performs to establish involved the determination are presented the Cement Portland ratio) ratio of first 21, 1990 of laboratories. in the four materials. and within testing of the proficiency tests P-O01 in SHRP-LTPP tension test, while The scope FILE: of SHRP Portland (compressive different from the material The with and Poisson's thirteen December Sample Program was undertaken properties at elasticity, Analysis The test program of elasticity, DATE: Bill Hadley assclated strength) of _ test program components concrete _/ Lf concrete of the then assess variations core sample variance (ANOVA) the magnitudes of the (o2L_ and 0 2 respectively) for each property. Two replicate laboratories did not estimate cells another, are the modulus the summarizing of capability design were the various available 2602 Della_ to cores conduct were the and Polsson's not material estimate and Polsson's Lane to of elasticity this is not a major elasticity concrete for the two mixes and four material have in sets filled properties limitation. the (see sources provided tests. test Several each required therefore, Figure i). will not be fewer of variability • Telepho.4 512 1 327-4211 • Pax the compared degrees the ratio than for the compressive and tensile Austin, Texu the to some of the Since for of laboratories procedures ratio; However, to with data one of freedom modulus of strengths. 512 I 328-7246 o E d d _• d d _ d d d d d d _ d d d d d d T" Figure I. Concrete core proficiency sample test data. i ESTIMATION The impact OF VARIANCE experimental on how statistical the the property. From these computation variances Four mean laboratories memorandum which provided Analyses are determined of for variance each components material for Details to check The between about their the similarity for each material property of with B. strength The factorial have unknown; been tests shown revealed when compared all * in strength balanced. outllers FIEure these A in the data. and occur potential values the Other compressive 1 thirteen appear outliers to strengths in deviate of the same laboratories. alternatives outliers. First, variability inherent they in using different are likely to be possible may be the test an extreme operators within the which in different test causes manifestation procedure true, these values should be retained observations an from 1 is completely causes behind compressive with obtained two possible with The possible two were in Figure designated these The following justification this procedure variance were performed proceed. An analysis are the in a direct Strength mix from different other used the squares has properly sections. in Appendix A. in Appendix I and 9. substantially s--_-rize collected (02) can be estimated. review of the data values were should statistics laboratories compressive prellmlnary data approach following s-mmary reported laboratories. performed A and across laboratories Compressive analysis the are explained the results remain the expected (_LAS) and within These in the analysis in Appendix with which statistical presented along under behind briefly results table destgn concepts explained COMPONENTS program. of occurs the when laboratories. and processed of the two random tests If this were in the same manner Removing these would result in lower estimates of the process are data as the without variability than should be reported. On the from the other prescribed hand, the outlying experimental values procedures 3/ could or be may the result represent of deviations an error in ,. calculating the or actual are reasons found. Only identified as testing recording outlying in this manner data necessary the 1. expected mean square and solving between This component lower portion values, implies the significant estimated correct Contact A, standard deviation within for compressive The estimated within laboratory it variation, implies laboratories. similar From These between labs is F-3.15. it indicate some values Although between average for effect error to its are reported of the difference at the _ - 0.01 level. compressive and high strength strength levels, to be for ERROR. outllers, considers two of O2LaB is found testing this value at each the The strength measure the results across exists. the analyses large, Table 7 The from laboratory i. the final of variance omitting 13 of laboratories. outlier when of significance at this time concerning additional desirable is not extremely laboratories values there has been no determination first for is larger than the between are will be shown to be due to the possible The method and numbers value difference investigated. are to be an excellent _, the of the potential values for all compressive indlca_es Since in used the estimate A small F-ratlo variation difference with variation, test the variation does responsible LAB and MIX was not found is considered " 42748.9. 1 the "" strength. average Table confidently of variation average laboratories laboratory _LAB be laboratory source the between between that action. a commonly from the medium The interaction error(s) i. indicates to vary investigate strength for each in Table and therefore has been combined of repeatability status with 52 compressive from difference any an appropriate for o2tas and G2. I to observations components is u - (79630) 112- 281 psi which since to Appendix square Table which are expected been verified. data and the all in estimates of essential the two levels of the factor MlX is significant result have for variance the mean is establish As explained respective It eliminated. table of equating The should to consists as the variance values and of variance in Table calculating these is The analysis values. for erroneous laboratory presented numerical were the presumed '- Table I. Analysis of variance for compressive strength, all clara. °. DEGREES SOURCE OF FREEDOM SUM OF MEAN SQUARES SQUARE LAB 12 3007508.81 250625.73 MIX 1 15025275.08 15025275.08 38 3025940.42 79630.01 ERROR EXPECTED MEAN SQUARE Oa + 4OaUW Oa + _(MIX) Oa Variance Component u2_s 02 Estimate 42748.9 79630.0 DEGREES .. SUM OF MEAN SQUARES SQUARE 13 18032783.88 1387137.22 17.42 = lAB 12 3007508.81 250625.73 3.15 " MIX 1 15025275.08 15025275.08 188.69 " 38 3025940.42 79630.01 51 21058724.31 SOURCE OF FREEDOM MODEL ERROR CORRECTED TOTAL Q Significant at the 0.01 level. F-RATIO outlier when from laboratory omitting I, while the presumed The analysis outliers of variance MIX 2 from the laboratory the within laboratory gives an estimated of the between impact of estimates varlance testing from MIX 2 (laboratory Table 3. between laboratories, previous case. reduced since than data The within the estimated the expected Based I certain. standard number is an These established has the accepting of 66984.55. This result psl. The estimate to O2LAs -- 16616.8. a large The reduction in both of 5090 the values from Mix 1 (laboratory 9) is presented component nearly may be and significance the same variance, 02- considered as the 49754.7, normal core Tables for results for the has been further testing variation outlying the analysis is less tests. 2 and the in level of a - (49754.7) 1/2 - 223 psi whereas of made The estimate when omitting deviation from reduced of derived for concrete outlier status before table what too 2- 2. 5090 of variance. laboratory on the results laboratory value remain and now lles below in Table the results the value of O - 258.8 has been of the variance _LAB' from omitting deviation I) and 6335 The estimates 1 and 9. is presented variance of variance from laboratories has been reduced of the two components The analysis s-mmarizes derived standard one omitted analysis cable 1 results laboratory this the second 3 it is likely value from data values of variance the value laboratory needs results 9 to be from is less further in either Table 2 or Table 3. Tensile Strength The analysis strength of variance from twelve laboratories of the factor MIX on tensile ratio (F-26.08). effect and variance of the difference The between across laboratories _L_" in Table were estimated strength varlatlon, estimates in Table 4. is indicated components in tensile laboratory in the test results are presented strength These variance component for the tensile The significance 4 by the large after due to the factor 5167.96, is greater indicates than removing Fthe MIX. the variation the variation within Table 2. Analysis with of one DEGREES SOURCE variance possible OF FREEDOM for outlier cospressive SUM OF MEAN SQUARES SQUARE LAB 12 1585469.40 132122.45 MIX 1 15560753.72 15560753.72 37 2478428.45 66984.55 ERROR strength removed. EXPECTED MEAN SQUARE 02 + 3.92 _tU O_ + _(MIX) Variance Component _LAB 16616.8 02 66984.55 DEGREES SOURCE OF FREEDOM MODEL 13 Estimate SUM OF MEAN SQUARES SQUARE 17863230.37 1374094.64 LAB 12 1585469.40 132122.45 MIX 1 15560753.72 15560753.72 37 2478428.45 66984.55 50 20341658.82 ERROR CORRECTED * Significant TOTAL at the 0.01 level. F-RATIO 20.51 " 1.97 232.30. Table 3. Analysis of variance with two possible DEGREES SOURCE OF FREEDOM for compressive outllers removed. SUM OF MEAN SQUARES SQUARE LAB 12 1346096.76 112174.73 MIX I 16216287.41 16216287.41 36 1791170.68 49754.74 ERROR strength EXPECTED MEAN SQUARE 02 + 3.84 02LAS 02 + Q(MIX) 02 • ° Variance Component Estimate 02 16255.2 LAB 02 49754.7 DEGREES SOURCE OF FREEDOM MODEL 13 SUM OF MEAN SQUARES SQUARE 18395392.94 1415030.23 LAB 12 1346096.76 112174.73 MIX 1 16216287.41 16216287.41 36 1791170.68 49754.74 49 20186563.62 ERROR CORRECTED * Significant TOTAL at the 0.01 level. F-RATIO 28.44 * 2.25 325.92 * laboratories (o _ - standard 2046.59) deviation is by estimated indicated by the siEnlficant test scores when for subsets of differences in average ModuIus relatively narrow techniques scale, roundoff Results modulus difference Including was found this factor for between laboratory larger than the within result indicates This difference (F-18.74). modulus is Results Polsson's are glve ratio. the small wlth variance component larger than the within result indicates is also indicated ratio digits given and lie in a and mixes. Since are reported of In analysis data variance the effect on a test results (F-13.82). two types are estimated. is nearly across the large of The five times This laboratorles. F-ratlo across 5 for a significant (o2 - 0.04176). of measurements 5 by that of the or testing component in Table in Table elasticity for LAB laboratories for 7. analyses F-ratlo of variance for MIX reported indicates difference was found for this factor on Polsson's ratio laboratory 7 s---,=rlzes the response (G2LAB - 0.19077) in average in Table be different and Folsson's indicates modulus removes component indicated from The factor due to laboratories The differences are summarized for MIX of uniformity also Therefore, estimates. of variance F-ratio laboratory a lack also and a very small range of data may not give the variance is Ratio efficiently in the model mixes before the variation will across all laboratories found from the analysis The testing feature Table of elasticity most errors the In Table 4. together. of these variance of elasticity. This only a small number of values. work estimates 45.24. data for tensile strength. range when compared of very accurate this to only one or two significant the data assume continuous From across laboratories grouped for modulus this analysis variance O - and Poisson's in Figure 1 were reported 2 1/2. for LAB (F-10.88) test results The values reported be compared laboratories of Elasticity of to F-ratlo the average the a factor (_L_ laboratory variance a lack of uniformity in the analysis " 0.0011805) of measurement of variance table that no (F-O.02). IS more component In Table slgnlflcant The between three times (02 - 0.0003537). This across than 6 for laboratories and for the factor LAB ( F - Table 4. Analysis of DEGREES SOURCE variance for SUM OF OF FREEDOM tensile strength. MEAN SQUARES EXPECTED SQUAFI MEAN SQUARE LAB 11 244959.23 22269.02 o2 + MIX 1 50778.59 50778.59 oa + 34 69583.93 2046.59 ERROR "" 3.913 O2u_ _(MIX) o2 Variance Component o 2LAB 5167.96 0.2 2046.59 DEGREES SCIURCE IAB MIX MEAN SQUARES SQUARE 12 295737.82 24644.82 12.04 II 244959.23 22269.02 10.88 " 53381.49 53381.49 26.08 34 69583.93 2046.59 46 365321.74 1 ERROR CORRECTED " Significant SUM OF OF FREEDOM MODEL TOTAL Estimate at the 0.01 level. F-RATIO " .. Table 5. Analysis DEGREES SOURCE OF FREEDOM of variance SUM OF MEAN SQUARES SQUARE for modulus. EXPECTED MEAN SQUARE LAB 8 6.2591 0.78239 02 + 3.8824 02L_ MIX 1 0.5114 0.51144 02 + 25 1.0439 0.04176 02 ERROR _(MIX) Variance Component SOURCE Estimate 02u_ 0.19077 oa 0.04176 DEGREES SUM OF MEAN OF FREEDOM SQUARES SQUARE F-RATIO MODEL 9 6.7705 0.7523 18.02 " LAB 8 6.2591 0.7824 18.74 ° MIX 1 0.5772 0.5772 13.82 * ERROR 25 1.0439 0.04176 CORRECTED TOTAL 34 7.8145 • Significant at the 0.01 level. Table DEGREES SOURCE OF FREEDOM 6. Analysis of variance for Polsson's SUM OF MEAN SQUARES SQUARE ratio. EXPECTED MEAN SQUARE LAB 5 0.024306 0.004861 02 + 3.8182 G2LAB MIX i 0.00000952 0.00000952 o2 + 0.005659 0.0003537 O2 ERROR 16 _(MIX) .. Variance Component 02 _B 0.0011805 0_ 0.0003537 DEGREES SUM OF MEAN SQUARES SQUARE 6 0.024315 0.0040525 11.46 * IAB 5 0.243056 0.048611 13.74 * MIX 1 0.00000784 0.00000784 16 0.005659 0.0003537 22 0.029974 SOURCE OF FREEDOM MODEL ERROR CORRECTED * Significant Estimate TOTAL at the 0.01 level. F-RATIO 0.02 Table ¢o_presslve 7. Analysis of laboratol_" means. Strength LAB: 9 10 2 6" 11 5 12 8 3 6 7 13 1 MF..a_: 6181 610S 6082 6080 6035 6032 5995 5955 5901 5882 5860 5778 5185 GROUP : Tensile Strength LAB: 13 3 12 MEAN: 683 627 600 8 2 589 584 II 582 9 574 I 530 4 524 5 6 522 462 i0 404 GROUP: Modulus LAB: MEAN: 13 5.00 6 5 4.72 4.48 I0 9 II 12 4.21 4.17 4.16 4.12 2 3.75 7 3.59 GROUP: Poisson's LAB: MEAN: GROUP: Ratio 13 0.2525 "- 5 0.2433 6 0.2425 I0 0.2075 9 0.1875 12 0.1650 ratio for equals 13.74). Po_._son's ratio ILLUSTRATING test Differences are If two sample means results two population means the two-sample available from more including its true means? If each all tests have a probability. therefore two the requlre 7 to be Groups of concerned continuous suggest are llne does the true deviation to difference. which from lle means from Nontransltlve confidence means an are is of the respective is significance to control the different. comparison results. one another. on either these sample also. this of two means and which The average from exceed test largest to indicate which The averages to be end of the row. averages, are Probability concerning are underlined intervals, occur their in a row and ranked are necessarily results each that either the means laboratory insufficient then all of them having limits and do not conform these that that for the probability contain different means different interval Interpretatlons not appear underneath do not imply the population it indicates make are presented those control When interpreting rather used with If data are What comparisons of tests. the true level _, then the probability than for a single laboratory most mean. from the is tested interval. each giving the conclusion statistically are not statistically with than they whether a confidence simultaneously types from each laboratory about to one another population that are computed a confidence multiple alternative ones standard of reaches are producing to smallest. inferences are equal u is less goal special is then test has the significance needs to be stronger laboratories to will laboratories COMPARISONS deviations be constructed, intervals across 7. laboratories, true The procedure Table results than results MULTIPLE or by constructing The same versus statements laboratory significance alone. Table MEANS: corresponding that all test and their standard as easily probability in laboratories, t-test can Just level AMONG of each laboratory the s-mm_rized DIFFERENCES from in average there the If one is evidence two or three to the rest of the data. means which equal size For are underlined to one another was used example, equal; to detect if the a row "- contains may be middle seven values, significantly the three different from may not be siEnlflcantly these means belong largest means one another, different to both groups and which the yet three the from each other smallest four means means even in though the some of are different. "- SUMMARY Test across equal results all compressive laboratories to the laboratories Polsson's value One possible when using the consequence were within Large found to laboratory variations cause for these specialized in estimating from the analysis be in results test same nearly across of elasticity, are differences evaluate properties of variance presented and in these material to further these material the was results tests to estimate laboratories nearly variation strength, the modulus A query of the cooperating of the differences a direct that expected. procedures properties. and strength were found for tensile ratio. laboratory extent for here. the should be REFERENCES I. Dixon, W.J., and Massey, Ed., McGraw-Hill, 2. "Conducing F.J., Int_oducV$o_ New York, Analysis, 3rd N.Y., 1969. an InterlaboratoryTest Test Methods V@ Statistical for Construction Program Materials', to Determine ASTM the Precision Standard Practice of C 802- 80. 3. "SAS User's Guide: Statistics', Version 5, SAS Institute, Cary, NC, 1985. 4. Milliken, Learning G. A., and Johnson, Publications, Belmont D. E., Analysis Californla, of Messy Data, Lifetime 1984. • t APPENDIX A EXPERIMF__AL The design of the were controlled The layout and are assumed of the factors primary variables, space experiment relative statistical their laboratories analysis. includes to account and to this study two classification for variations levels is shown variables and serve in Figure as the independent results which in the test results. 1. (LAB) and mixes (MIX), represent Inconclusive to occur if other variables, DESIGN The two the inference variables from this experiment in the are which were not measured or controlled, likely influenced the results. FACTOR CLASSIFICATIONS The experimental since the requires data design used to relate these factors requires collection the application is classified plan implies of specific as either fixed and also by the definition A variable is defined in the test plan. were chosen levels. as entire to be fixed medium difference between A factor is designated population included of to be designated as having computed. made Each primary The decision to designate and variable an effect of the study or interest a random random if all levels of interest only two levels of MIX were high strength which are included defined. implies two to be fixed and an effect They specific summarizing the two levels can be computed. as random are chosen at random. considered be of the factor. The factor MIX is designated the average can on the inferential objectives In this analysis either inferences analysis methods. or random. in one of these two ways is based what explanation are whenever included only a few elements in The laboratories sample effects of .. the design, and chosen for this all possible from the component ones design are They are laboratories. and the variance the o_m will be Factors defined the whose levels as crossed levels of possible to appear with one MIX and find any for LAB are within each variance ability used for an this the of objective variances which separated into effects of with one of these levels mix. of the factors proposed another two Two the pure error, _, it is .. how the error in were made the analysis of s-mmarlzes the which for the same design factors. measurements used are since determines The method themselves variance cannot parts laboratories). The (one random component be measured assignable model and of _ directly. interest laboratory one fixed). _ and mix. total sources deduce variation (between two-factor model values of is to be and with within mixed is: + ai + _j + _ijk - mean of the ith laboratory Ej - effect of the jth mix _ijk " residual of components square from then solving commonly (fixed) used for between each source for OZLAB and GZ. component (random) (random) the most mean variance to The form of the model - effect variance is The is the ai One analysis to different Yijk " estimates methods for calculating and within laboratory of variation These provided to its two numbers in Tables (I-1, .... 13) and T be their the expected components average. of the mean have the following squares values: the respective consists of equatlngthe expected mean are reported I through Let T|.. -_s_-Yij k, the sum of all measurements data in in this test plan each remaining reason, is estimated. estimate the COMPONENTS The where level crossed of of the tests to repeat VARIANCE all laboratory laboratory provides For combination the within every another. The type of replication term with made Then it can be and in the set of 5. in the ith laboratory shown for laboratories square and that for balanced for the residual .. E [MSLABS ] -- E [ _ (Z|.. E [MS.s:] - E [ _ To calculate variance their as the variance given expected in mean squares, For unbalanced slightly Tables data different. 2 through properties; This 6. still be reasonable 1 through and solve - 0 _ + bn 02LAB 02 and 02LAs, compute 6, these _o set the situation occurred components analysis equal of the two equations in the analyses data points of the true values. of to simultaneously. s-mmarlzed will loose some of their if the number of missing good estimates the expressions two equations the factor bn in the first The variance however, ] (Y_Jk" y)Z ] . oZ components Tables T)2 is small is in optimal they will APPENDIX An important the similarity The part determine a thorough of measurement investigation variations of within analysis variances initially assumes different of this data (homogeneity) the laboratories if there is sufficient B hypothesis to reject to within that are the same. evidence is investigate laboratories. all measurement The objective this hypothesis is to based on the observed data. Estimated variances the following formula within each of the laboratories for all four material - from the ith laboratory of test results The data used for these calculations refers to the ith laboratory Tables estimated these values Table variances are based should not be B-I the variances of 200 in laboratory within is the consequence 174,050 considered 5 to a high of in MIX 2 is considerable Although not nearly determination wide accurate strength 1. The subscript subscript and ranges outlier. J refers most three are listed of values. estimates. (Nij i to 9. in Since i) - I), For example, from MIX 1 range in from a low An even wider This large variance from MIX The second largest variance larger than the remaining of these numbers mix (i.e., in laboratory is observed. alone variances. some major Based differences in likely exist. as severe, of the other laboratory of 415,872 a possible laboratory variation in Figure on one degree of freedom of compressive on the visual observations within each are observed range for MIX 2 of 800 to 793,800 2 are given and the jth mix 2 (J - 2). B-I through B-4 from which these computations and the j_h mix from the ith laboratory (i - 1 ..... 13) and the either MiX 1 (J - I) or MIX The - i) [ E Yijk2 - NijYij2 ] / (Nij - i) where Yijk " the k th observation Nij - the number using tests: (Y|]k " Yi])2 / (Nil O_j2 -Z were calculated wide ranges in variances material properties also exist in the as well. Whenever only "" one observation (NIj - i) was available it deficiency was not three observations, sample sizes, maximum already normality calculate B-2, B-3, have not work observed with leads to the makes more variation efficient of the of variances power when in each laboratory, require working at least with small In this study, from each cell. The wide range conclusion that the assumption tests for homogeneity a of of of variances of sent to each laboratory, the within data. This laboratory method will be the same for both MIX 1 and MIX 2. the two mixes the formula variance assumes Combining to compute it is the which testing the data this pooled from estimate is: oi/where - 1) * oi_z+ NS - (nil + ni2 - 2). previous estimates each mix. pooled estimate rather where is divided the by 2. This of compressive the two They are based homogeneous laboratories. and material are more Values identified, strength, are the reasonable quite number average of tests of the two performed on previous estimates on two degrees within each of freedom (NS - 2) appear be efficiency. pooled than for laboratories still is a weighted sizes are the same for each mix so the than one and have much greater For - 1) * OizZ] / NS are the the sample sum (nil estimate the weights In this analysis laboratory were [(nil .. and B-4 by a blank. mixes were estimate use This are not feasible. Since two cores from different a pooled variance. data. Therefore, methods estimated nonnormal were available on these statistical compute an sufficient well may not be Justified. possible for any of these three properties tests for the homogeneity do not or do to in Tables of two replicates values based possible is indicated Most statistical from any cell the individual i and 9, where large. tests are much more comparable estimates Estimates to estimates the potential from to one another. the more for all outllers other three ° Table B-I. Within laboratory variances COMPRESSIVE MIX 1 LAB! 1 2 3 4 5 6 7 8 9 10 11 12 13 Nil-1 1 1 1 1 1 1 1 1 1 1 I 1 1 Table B-2. Oil 12 Within 1 1 I i I I I 1 i 1 1 i i laboratory MIX i I 2 3 4 5 6 8 9 10 11 12 13 Nil-1 I I 1 0 1 1 1 I 1 1 1 1 0i112 968.0 4512.5 40.5 450.0 312.5 0.0 420.5 162.5 200.0 50.0 3528.0 POOLED ai12 2 Ni2-1 145800.0 22050.0 92450.0 1800.0 200.0 22050.0 9800.0 96800.0 415872.0 105800.0 14450.0 168200.0 6050.0 NS 793800.0 33800.0 49612.5 1250.0 11250.0 48050.0 7200.0 12800.0 49612.5 20000.0 174050.0 3200.0 800.0 variances 2 2 2 2 2 2 2 2 2 2 2 2 2 - Tensile 1 I 1 1 1 1 1 1 1 1 1 1 a1_ 469800,00 27925,00 71031,25 1525 00 5725 O0 35050,00 8500,00 54800,00 232742.25 62900.00 94250.00 85700.00 3425.00 Strength. STRENGTH MIX 2 Ni2-1 Strength. STRENGTH MIX 2 TENSILE LAB i - Compressive POOLED Oi122 NS 364.5 50.0 3698.0 264.5 50.0 112.5 112.5 924.5 2.0 1250.0 1250.0 1200.5 2 2 2 1 2 2 2 2 2 2 2 2 Oi_ 666.25 2281.25 1869.25 264.50 250.00 212.50 56.25 672.50 82.00 725.00 650.00 2364.25 Table B-3. Within laboratory variances MODULUS Nil-1 2 5 6 7 9 I0 II 12 13 1 1 1 1 1 1 1 1 1 0tll 2 0,005 0,005 0,045 0 0025 0 0041 0 005 0 045 0 005 0 0113 Table B-4. Within MiX 2 Ni2-1 Oi12 2 1 0 1 1 1 1 1 1 1 0.0 0.0 0 0 0 005 0 0313 0 0013 0 02 0 0113 laboratory variances POISSON'S MIX I LAB i Nii-I 5 6 9 I0 12 13 1 1 1 1 1 1 Oill 2 00005 00125 0002 0002 00005 0002 of Elasticity. OF ELASTICITY MIX 1 LAB i - Modulus POOLED NS 2 1 2 2 2 2 2 2 2 0 1 1 1 1 1 Ratio. RATIO Oi122 .0 .00005 .00005 .00045 .00005 S/ 0.0025 0.005 0.0225 0.01225 0.0045 0.0181 0.0231 0.0125 0.0113 Poisson's MlX 2 Ni2:l Oip2 POOLED NS Oip2 1 2 2 2 2 2 .00005 .00063 .000125 .000125 .000400 .00025 . APPENDIX VII • TECHMEMO: AU-127 (Addendum Precision Robin High, Virgil Precision Statements AUTHORS: SUBJECT: Proficiency The core within _onn._ _. results presented modulus of The SHRP that and value random from type impl_es each of Compressive the the laboratory core by - The Construction 2602 DeUana SHRP the concrete AU-127 dated 5as_d _,^n the _tate=_nts, stength, CONCRETE are The standard from the same between differ from tensile than 2 2 G CORE based strength, SAMPLES on the results standard deviation deviations limits laboratory one another wlthin.-laboratoryslngle results in should not represent, C670, strength operator sample Practice preclslcn FOR two more for only are of for given. selected measurement made _,e an the This measurement 5% for on at the time. Strength same ASTM Core Memorandum compressive difference _I11 Therefore: ' Technical cores. observations compressive numbers 1991 Concrete components statements sample that concrete Precision These 19, ratio. precision and two for STATEMENTS proficiency between latter in Polsson's PRECISION measurement difference March Cement variance given report, wlthin-laboratory individual same laboratory were elasticity, concrete Portland ,_,-..,._ a_-_.._-_-_"pro--Ide= in WITHIN-LABORTORY Statements)_(_ Anderson]_Y" for SHRP between samples 21, DATE: Samples and proficiency D_.cember - for has of the been two Precision more IS and to deviation be a conducteG laboratory by the stan_rd found properly same differ respectively, Preparing operator on the same 2 _G - D2S limits as for 258.8. tests than Statements - Test by Aura.in, Temm • Te/ephoee 512 I 32"/-42_! • Fix 512 the concrete 732.0. described Methods Materials. lane for I _2942,.i6 in for Tensi_ Strength Precision - The wlthln-laboratory single operator tensile strength has been found to be a - 45.24. results of two properly in the same laboratory differ These numbers represent, AST_ C670, Practice Construction Modulus by more Therefore, tests by the same operator on the same concrete sample should not than 2 v_ o - 128.0. respectively, for Preparing the lS and D2S limits as described Precision Statements in for Test Methods for standard deviation for of Elasticity - The within-laboratory modulus of Therefore, same numbers Practice Construction Poisson's C670, results should represent, single operator elasticity operator sample ASTM conducted for Materials. Precision These standard deviation of has in the same for Preparing found two properly not differ respectively, been be o conducted laboratory by more to than on - tests the same 2 _O 0.204. by concrete - 0.578. the IS and D2S limits as described Precision Statements the in for Test Methods for standard deviation for Materials. Ratio Precision - The within-laboratorysingle Polsson's results Ratio has been of two properly in the same laboratory differ These numbers represent, ASTM C670, Practice Construction by more found respectively, to be a - 0.0188. conducted Therefore, tests by the same operator on the same concrete than 2_o for Preparing Materials. operator sample should not - 0.0532. the IS and D2S limits as described Precision Statements for Test Methods in for BETWEEN-LABORTORY PRECISION STATEMENTS The between-laboratoryvarlance given in Technical standard deviations different between differ Memorandum limits laboratories one measurement are FOR SHRP CONCRETE components AU-127, are derived selected These between imply two two observations that from the difference at random from each of two laboratories _T,ebetween-laborato_ys!ngle compressive 289.14. strength Therefore, from one concrete will + o2) only 5% the time. has operator standard deviation been the results sample These numbers represent, respectively, ASTM Practice C670, for Preparing Construction Materials. found to be of properly conducted (O2L_ + 02 ) - 817.81 tests should from each the iS and D2S limits as described Precision Statements for _OaLA B + O2 . in each of two laboratories not differ by more than 2 V2 other. for Test in Methods for operator standard deviation for Strength Precision - The between-laboratoryslngle tensile strength Therefore, has been the results found to be _O_LA s + 02 -- 84.94. of properly conducted concrete sample in each of two laboratories by more These numbers ASTM The Strength Precisl_n Tensil in this section. values from each other by more than 2J2(o2L_ Compressive SAMPLES fort he concrete core samples, for the difference given. CORE Practice Construction represent, C670, than 2 respectively, for Preparing Materials. 2 (O2 tests from one should not differ + 02 ) - 240.24 from each other. the IS and D2S limits as described Precision Statements for Test Methods in for Modulus of Elastl¢i_y Precision - The between-laboratoryslngle modulus of elasticity Therefore, concrete by more These numbers represent, the has results sample than in each 2 J2 been of standard found properly the conducted " 1.364 Statements for - 0.482. tests should from each IS and D2S limits Precision deviation to be of two laboratories (02LAS +02) respectively, ASTM Practice C670, for Preparing Construction Materials. Polsson's operator from not one differ other. as described in for Test Methods for single operator standard deviation for Ratio Precision - The between-laboratory Poisson's ratio Therefore, concrete by more These numbers represent, ASTM C670, Practice Construction the results sample found to be of properly _02LAS + 02 - 0.0392. conducted in each of two laboratories than 2 _2 (O2LA s +02) respectively, for Preparing Materials. has been -- 0.1108 Statements should not differ from each other. the IS and D2S limits Precision tests from one as described for Test Methods in for APPENDIX Vlll March W. Charles Greer, Law Engineering 396 Plasters Avenue Atlanta, GA 30324 Dear 26, 1990 Jr. NE Charles: Subject: SHRP PCC Core Proficiency Sample Program. I am pleased to advise that SHRP, based upon test results from the subject program, has authorized your laboratory to proceed with the testing of portland cement concrete (PCC) cores from field sections of the LTPP project in accordance with required protocols. It was noted that your laboratory achieved a rating of five, using the Cement and Concrete Reference Laboratory (CCRL) approach to analysis, on all tests included in the subject program. This was indeed an excellent performance. As you proceed with these tests on SHRP field samples, the same internal quality control practices should be followed that were used when testing the PCC proficiency samples, thus providing confidence in the data generated. Yours very truly Garland W. President, cc: Steele, Steele Adrian Box P.E. Engineering, Inc. Pelzner 173 • Tornado, West Virginia 25202 • Tele. (304) 727-8719 $ 13 LABS PARTICIPATE IN SHRP PCC CORE PROFICIENCY SAMPLE PROGRAM Final results of the Portland Cement Concrete Core Proficiency Sample Program were recently forwarded to the 13 participating laboratories by the Iowa Department of Transportation Office of Materials. Over 150 4" by 8" cores were shipped for determining the precision of tests to be performed on concrete pavement cores from the LTPP study. The program was designed to obtain data on the static modulus of elasticity, poissons ratio, splitting tensile strength, and compressive strength. Detailed data analysis is now under way by statiscal consultants at TRDF. However, preliminary data analysis and laboratory ratings were determined using the widely recognized Cement and Concrete Reference Laboratory (CCRL) approach i. The best laboratory rating under this proceedure is a 5, indicating that a laboratory's test result is less than one standard deviation from the mean of all results. The preliminary analysis indicated concrete testing (Law Engineering, in each category of the program. SHRP has directed Law to proceed LTPP field samples. Laboratories participating Florida Transportation, FL Department of Gainesville, Iowa Department Transportation, Ames Federal Administration, , Highway CO of CA Department Charleston, of WV Engineering, Atlanta, GA National Aggregates Association/National Ready Mix Concrete Association, Silver Springs, MD i 1959 ASTM this program Bureau Co were: of Waterways Vicksburg, Reclamation, Experiment MI Denver, Station, IA Department Sacramento, West Virginia Transportation, Law of Denver, California Transportation, in that the SHRP laboratory for Atlanta) achieved a 5 rating Based upon this performance, with the concrete core tests on Proceedings, Concrete Technical CANMET, Canada Materials Services, Skokie, Ottawa, Wiss, Janey Northbrook, IL Ontario, and New York Department TranspoM_t_o_,AiB_y, W. Charles Greer, Jr. Law Engineering S96 Plasters Avenue NE Atlanta, GA 30324 Crandall and Blaine and IL paper. Elsner, of NY Compressive Strength Precision The within-laboratory single operator standard deviation for compressive strength of PCC cores has been found to be a = A258.8. Therefore, results of two properly conducted tests by the same operator in the same laboratory on the same concrete sample should not differ by more than 292 a = _732.0. The between-laboratory compressive strength {(a_lah+a:) = A289.14. tests from one concrete not differ by more other. single operator standard deviation for PCC cores has been found to be Therefore, results of properly conducted sample in each of two laboratories should than 2{(2(a:iab+a2)) = B817.81 from each of These numbers represent, respectively, the as described in ASTM Practice C670, Statements for Test Methods for Construction Splittinq Tensile ADIS and Preparing Materials. _D2S limits Precision Strenqth Precision The within-laboratory single operator standard deviation for splitting tensile strength of PCC cores has been found to be a = A45.24. Therefore, results of two properly conducted tests by the same operator in %he same laboratory on the same concrete sample should not differ by more than 292 a = _128.0. The between-laboratory single operator standard deviation for splitting tensile strength of PCC cores has been found to be {(O21ab+O2 ) = A84.94. Therefore, results of properly conducted tests from one concrete sample in each of two laboratories should not differ by more than 2{(2(a21ab+a2)) = B240.24 from each other. These numbers as described Statements for & represent, respectively, the in ASTM Practice C670, Test Methods for Construction ADIS and Preparing Materials. 5D2S limits Precision 4 Modulus of Elasticity Precision " The within-laboratory single operator standard deviation for modulus of elasticity of PCC cores has been found to be a = A0.204. Therefore, results of two properly conducted tests by the same operator in the same laboratory on the same concrete sample should not differ by more than 2q2 a = 50.578. The between-laboratory modulus of elasticity q(a_[_b+a_) tests from not differ = _0.482. one concrete by more than single of PCC operator cores standard has been for be Therefore, results of properly conducted sample in each of two laboratories should 2_(2(a21_+a_)) = 51.364 from each other. These numbers represent, respectively, the as described in ASTM Practice C670, Statements for Test Methods for Construction Poisson's deviation found to _DIS and Preparing Materials. _D2S limits Precision Ratio Precision The within-laboratory single operator standard deviation for Poisson's ratio of PCC cores has been found to be a = _0.0188. Therefore, results of two properly conducted tests by the same operator in the same laboratory on the same concrete sample should not differ by more than 2_2 a = _0.0532. The between-laboratory Poisson's ratio of A0.0392. Therefore, single operator PCC cores has been results of properly concrete sample in more than 2_(2(_21ab+_2)) each of = standard deviation found to be _(a21ab+a2) conducted tests from two laboratories should 80.1108 from each other. These numbers represent, respectively, the as described in ASTM Practice C670, Statements for Test Methods for Construction not ADIS and Preparing Materials. differ for = one by _D2S limits Precision Long-Term Pavement Performance Advisory Committee Chairman Marshall 1_ Thompson William J. MacCreery W.J. MacCreery, lnc. University of Illinois David Albright Exxon Chemical Kenneth P_ Wardlaw t Alliance for Transportation Corporation Research Marcus Williams Richard Barksdale Georgia Institute H.B. Zachry Company of Technology " Liaisons James L. Brown Pavement Consultant Albert J. Bush, III USAE Waterways Experiment Robert L. Clevenger Colorado Department of Highways Station Louis M. Papet Federal Highway Administration Ronald Collins Georgia Department of Transportation John P. Hallin Federal Highway Administration Guy Dore Ministere des Transports de Quebec Ted Ferragut Federal Highway Administration Charles E. Dougan Connecticut Department of Transportation Frank R. M¢Cullagh Transportation Research Board MeRaney Fulmer South Carolina Department of Highways and Public Transportation Expert Task Group Paul E. Bcnson Marlin J. Knutson American Concrete Pavement Association Hans Jorgen Erlman Larsen Danish Road Institute, Road Directorate California Department of Transportation James L. Brown Pavement Consultant Lyle Calvin Oregon State University Kenneth H. McGhee Consultant Civil Engineer John P. Hallin Raymond K. Moore University of Kansas Federal Highway Administration Newton Jackson Richard D. Morgan National Asphalt Pavement Washington State Department of Transportation Association Alex Kazakov William IL Moyer Pennsylvania Department of Transportation Ontario Ministry of Transportation Walter P. Kilareski David E. Newcomb University of Minnesota Pennsylvania Transportation Institute Richard A. Lill Charles A. Pryor National Stone Association Robert L. Mason Southwest Research Institute Cesar A.V. Queiroz The World Bank William D.O. Paterson World Bank Roland L. Rizenbergs _ Kentucky Transportation Cabinet Gary K. Robinson Arizona Department Federal Highway Administration of Transportation Department of Transportation Ted M. Scott American Richard M. Weed New Jersey DOT Frederic R. Ross Wisconsin James A. Sherwood Trucking Association Amir N. Hanna SHRP Staff
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