Concrete (56) PROFICIENCY TESTING PROGRAM REPORT

Transcription

1 Concrete (56) PROFICIENCY TESTING PROGRAM REPORT Accredited for compliance with ISO/IEC Copyright: LabSmart Services Pty Ltd Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 1 of 39

2 Report This report is available on the LabSmart Services website. The issue of this proficiency report was authorised by Peter Young, Director, LabSmart Services Pty Ltd, February Contact Details Mobile: Fax: (03) Program Coordinator The program coordinator for this program was Peter Young, Director, LabSmart Services Pty Ltd. Contact Details Mobile: Fax: (03) Accredited Proficiency Testing Provider LabSmart Services is accredited by NATA to ISO/IEC 17043, Conformity assessment General requirements for proficiency testing. Accreditation number The accreditation provides additional assurance to participants of the quality and importance we place on our proficiency testing programs. LabSmart Services As well as proficiency testing programs LabSmart Services also offers a wide range of other services including consultancy, training and nuclear gauge calibration. Please see our website for further details. Copyright This work is copyright. No part of this publication may be reproduced in any form, transmitted or stored in any repository (e.g. mechanical, digital, electronic or photographic) without prior written permission of LabSmart Services Pty Ltd. Please contact LabSmart Services should you wish to reproduce any part of this report. Amendment History Reports may be downloaded from the LabSmart Services website. Version 1 Issued 20 February 2015 Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 2 of 39

3 CONTENTS PAGE 1. Proficiency Program Aim 4 2. Performance 2.1 Identified Outliers 2.2 Overall Performance 3. Technical Comment 3.1 Compression Strength 3.2 Mass Per Unit Volume 3.3 Intermediate Parameters 4. Statistics: Z-Scores & Graph 4.1 Sample A - Compressive Strength 4.2 Sample A - Mass per Unit Volume 4.3 Sample B - Compressive Strength 4.4 Sample B - Mass per Unit Volume 5. Program Details 5.1 Program Design 5.2 Sample Preparation 5.3 Packaging and Instructions 5.4 Quarantine 5.5 Dispatch 5.6 Homogeneity Testing 5.7 Participation 5.8 Statistics Summary of Participant s Results 6.1 Sample A 6.2 Sample B Appendix A Statistics - Intermediate Parameters A-1 Height A-2 Average Diameter A-3 Weight A-4 Maximum Force Appendix B Instructions for testers Appendix C Results Log Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 3 of 39

4 1. Program Aim The proficiency program was conducted in November The program involved the performance of: AS , Determination of the compressive strength of concrete specimens and AS , Determination of mass per unit volume. The program provides feedback and confidence to the construction materials testing industry regarding the competency of participants (and the industry) to perform these tests. Each participant s performance is statistically assessed and used as a measure of competency relative to all those who participated. This report has been prepared using a robust statistical approach. In addition data has been reviewed for consistency and additional feedback regarding aspects of the test are provided. Comprehensive technical comment is provided to assist participants improve the overall performance of this test. 2. Performance 2.1. Identified Outliers Overall a satisfactory level of testing was achieved by the majority of participants, most not listed below had z-scores between -1 and 1 which is considered an excellent result. Outliers were classified as z-scores where the absolute z-score value was greater than 3. There were six participants (15%) with outliers. Participants obtaining a z-score outside the range ± 2 may wish to consider reviewing their results. See table 2.1 below. Please note that only those participants with an absolute z-score great than 2.75 are shown in the review column. Participant s z-scores and graphs are detailed in section 4. Test Investigate (Outliers) Review Sample A Sample B Sample A Sample B Mass per unit volume T3 E7, T3 - S7 Compressive strength G5 Z2, B6, G5 - - Table 2-1 Statistical Outliers Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 4 of 39

5 It is recommended that participants consult the technical comment section (3) of this report. Some other participants whose results may not have shown as an outlier may need to investigate the result obtained. See table 2-2 below. Test Mass per unit volume Compressive strength Investigate Review Sample A Sample B Sample A Sample B Q6, L2 Q6, L2 G4, Z2, T3, W2 G4, T3, M5, W2 Q6 Q6 A7, T3 (L2), A7, T3 2.2 Overall Performance Table 2-2 Results requiring further investigation or review The overall performance by the vast majority of participants (85%) was very good. The spread of results (Variation) was well within industry expectations. Sample A gave an approximate standard deviation of 1.6 MPa and 2.2 MPa for Sample B. There were 44 participants in the program. The number of participants that failed to return results (4) in time to be included in the program reporting was disappointing. Sample A Sample B Statistic Compressive Strength Mass per unit volume Compressive Strength Mass per unit volume MPa kg MPa kg No of participants Median N-IOR CV (%) Range * Table 2 2 Summary of test results statistics. Range* excludes outlier results. There were a number of instances where test results had been calculated incorrectly. Quite a few participants returned only partial results. This is where a participant did not supply all the intermediate data or supplied the intermediate data but not the final result. Also a significant number (6) had the results for sample A transposed with sample B results. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 5 of 39

6 Although this is of concern it is perhaps more worrying that these errors were not picked up during the checking process. The compressive strength results for both Sample A and Sample B showed a very small variation. The mass per unit volume results showed a low variation for this test as well. The outcome was consistent with previous proficiency programs. Overall the results are well within industry expectations. The proficiency program demonstrated that the majority of participants were competent in performing these tests. 3. Technical Comment General A summary of results for all participants may be found in section 6. The reporting requirements under the Australian Standard are compressive strength and mass per unit volume. Outlier assessment was undertaken based on these results, the robust statistical analysis of these can be found in section 4 of this report. Appendix A details some statistics which may be useful in investigating any follow up action. Outcome Overall there was very good agreement amongst participants for both the Mass per Unit Volume and the Compressive Strength. The overall program statistics are similar to those obtained in previous programs. Despite the consistent results that were obtained there was a large number of errors in the calculation of results and inattention to detail. The majority of matters detailed below should have been picked up during the checking process. It also throughs doubt on how carefully the actual testing process was performed. Missing Information A number of participants did not supply all the necessary information required by the proficiency program. The lack of information provided often means that the feedback that can be given in these cases is often very limited. Participants should contact the program coordinator if they require further explanation as to what information is required. The information requested also is used to validate the results obtained. Participants need to be aware that proficiency programs may reject results if they do not conform to the program requirements. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 6 of 39

7 3.1 Compressive Strength Calculation of compressive strength From the reported diameter and maximum force the Compressive Strength results can be determined. This was done for each result and compared to the reported compressive strength. Generally good agreement was obtained. Recalculated results that differed by more than 0.5 MPa may require further review by participants. One participant detailed below was outside the 0.5 MPa limit set and may find it beneficial to review the results submitted. T3 Submitted Recalculated Sample A Sample B As compressive strength results are rounded to the nearest 1 MPa for reporting purposes an incorrect calculation can cause a difference of 1 MPa in the result reported. Compressive strength is calculated from Max Force x Cross-sectional Area. E.g. Compressive strength = F max x (π x (((D 1 + D 2 )/2)/2) 2 ) Unrounded values for diameter and force should be used when calculating the compressive strength. The value of pi used can also have an effect. Those using excel can use the pi() function. Those with calculators that do not have a pi function should use 333/106. The use of 22/7 does not have sufficient accuracy. Compressive strength results A number of participants supplied information but did not calculate the compressive strength. These participants are shown below. Participant L2 indicated cap failure but still needed to have calculated the compressive strength. This is a significant variation from the program requirements and should be investigated. Sample A Sample B Investigate Q6 L2, Q6 Statistical Outliers Participant G5 reported low compressive strength results and low crushing force results for sample A & B that showed as outliers in the program. The failure mode in both cases was normal. It may suggest an issue with the platens, centring of the specimens on the platens or handling/preparation of the test specimens. Both samples were end ground which should have negligible affect. However similar low results were obtained for homogeneity samples that were also end ground. Review of the grinding process may be Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 7 of 39

8 appropriate. The specimen showed no significant variations physically. Only one other participant ground the end but they also used a rubber cap and obtained satisfactory results. The mass per unit volumes for both samples were fine. The individual weights of each cylinder were however low but probably as a result of grinding. Participant Z2 reported a low compressive strength result and low crushing force result for sample B that showed as an outlier in the program. The cylinder was sulphur capped. The failure mode was noted as shear. As discussed below the mode of failure is unlikely to have caused the low results. There may have been an issue with the platens, centring of the specimens on the platens or handling/preparation of the test specimens. The specimen showed no significant variations physically or with the mass per unit volume. Participant B6 reported a low compressive strength result and low crushing force result for sample B that showed as an outlier in the program. The cylinder was rubber capped. The failure mode was noted as normal. There may have been an issue with the platens, centring of the specimens on the platens or handling/preparation of the test specimens. The specimen showed no significant variations physically or with the mass per unit volume. Variation in compressive strength AS provides some guidance with regards to the expected within laboratory precision of testing. It indicates that 2 cylinders tested at 28 days should be repeatable within 10% of the mean at a 95% probability level. The proficiency program looks at the variation over a number of laboratories and the above precision is not applicable. However the between laboratory variation would be expected to be greater than the within laboratory precision detailed above. The 10% precision estimate is still however useful for interpreting the outcome of the program. See table 3.1. Sample A Sample B Median Variation Estimate (10% of median) Standard Deviation Estimate (N-IQR) x Table 3-1 Comparison of expected and observed variation Table 3.1 indicates that variation is well below even the precision expected (i.e. of two cylinders tested within the same laboratory) than the variation by all the participants. It is reasonable to conclude that participant results are well within industry expectations. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 8 of 39

9 Failure Modes A small number of participants (Sample A 6 participants and Sample B 7 participants) reported abnormal failures (Shear) during crushing (see section 6). Those showing abnormal failure (Shear) are shown below. Sample A Shear Failure M6 Q8 Z8 A7 T3 E2 Sample B Shear failure Y2 J8 Z2 L2 (Cap failure) E4 A7 E6 Participant A7 showed shear failure for both sample A and B. There may be some benefit in checking the equipment and methodology used. Participant Z2 is the only participant that showed a significantly lower result compared to other participants who also noted shear failure. The spread of results of those showing an abnormal failure was not much different to those showing normal failure. There is no strong evidence to suggest that Shear failure values should be discounted or excluded from the data set. Equipment configuration, air voids, variability in compaction and aggregate distribution are only some of the factors that affect the mode of failure. Possible causes of abnormal failures might include capping and crushing practices, stability of the load frame (i.e. alignment, squareness and rigidity) as well as the correct working/alignment of platens. Participant L2 reported a cap failure and did not report the compressive strength. Base on the data submitted the compressive strength was 47.1 MPa with a z-score of Although not an outlier it is on the low side and would be considered a suspect result pending further checking. The abnormal failure was most likely affected the result obtained. The effect the mode of failure has on the compressive strength result is difficult to determine except in obvious instances where an unrealistically low result is obtained. Late crushing Cylinders were cured past 28 days prior to despatch, so limited strength gain would be expected if cylinders were tested late. There were seven participants that did not test on the nominated date of 19 November. Most were less than a week overdue with only one tested later on the 4 December. There appeared no discernible increase in strength with results centring on the median value for both sample A and B. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 9 of 39

10 Capping Methods 31 participants used rubber caps (77%) with 8 participants (13%) using sulphur capping. There were two participants that ground the end with one of these using a rubber cap as well. The compressive strength statistics were recalculated for both sample A and B with sulphur capping only and Rubber capping only results. There was little difference noted between the two capping methods. Previous proficiency programs have not encountered any adverse correlation between reported compressive strength and capping method. Both rubber and sulphur capping are considered to yield equivalent results and were analysed as a group. 3.2 Mass per unit volume Calculation of mass per unit volume From the reported height, diameter and weight the mass per unit volume result can be determined. All participants mass per unit volume results were recalculated based on the intermediate data supplied (see Appendix A). Some variation was expected due to rounding etc. This was done for each result and compared to the reported mass per unit volume. Generally good agreement was obtained. Recalculated results that differed by more than 9 kg/m 3 may require further review by participants. One participant detailed below was outside the 9 kg/m 3 limit set and may find it beneficial to review the results submitted. Code Sample A Sample B Submitted Recalculated Submitted Recalculated G Z T W M The test method requires mass per unit volume result to be rounded to the nearest 20 kg/m3. In many of the cases shown above the difference may not have an impact on the result reported. However it is still important that the calculation process is correct and consistent. In some case it appears a transcription error may have been made. Instructions on the calculation can be found in Section 8 of AS It states that the mass per unit volume is the mass divided by the cylinder volume. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 10 of 39

11 The volume of a cylinder is given by V= πhr 2 where h is the cylinder height and r is the average radius, (i.e. Half the average diameter). Measurements should be in meters to achieve the reported MPUV in kg/m 3. Please see comments regarding the use of pi under the section on compressive strength. Mass per unit volume results Two participants (L2 & Q6) did not report the mass per unit volume. Based on intermediate data the mass per unit volume values are: Q6 - Sample A: 2369 kg/m 3 L2 - Sample A: 2379 kg/m 3 Q6 - Sample B: 2373 kg/m 3 L2 - Sample B: 2363 kg/m 3 These results give satisfactory z-scores however by not calculating the results it is a significant variation from the program requirements and should be investigated. Sample A Sample B Investigate Q6, L2 Q6, L2 Statistical Outliers Overall a satisfactory level of testing was achieved by the majority of participants for mass per unit volume. There was one outlier for Sample A (T3) and two outliers for Sample B (E7, T3). These participants need to review procedures and equipment used to ensure that laboratory practice is satisfactory. Reporting of cylinder weights Some participants cylinder weights were reported in grams instead of kg (see section 6). Converted values are shown in section 6 of the report. Participants need to ensure they follow proficiency program instructions. Conversions were undertaken as these values were used to verify the participants reported MPUV results. 3.3 Intermediate parameters There are a number of intermediate parameters which are measured in order to be able to calculate the mass per unit volume and compressive strength. The intermediate parameters are height, diameter, weight and maximum force. As the intermediate parameters are not required to be reported by the test method and may vary due to allowable variations in the concrete cylinders (moulds) they are not considered statistically as part of the proficiency program. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 11 of 39

12 This information however may prove useful where an outlier result occurs for mass per unit volume and/or compressive strength. For this reason analysis of these intermediate parameters has been included in Appendix A-1 (height), A-2 (average diameter), A-3 (weight) and A-4 (maximum force). Appendix A is provided for information only. The z-score are there as an aid to assist with identifying possible issues and their resolution. Any outliers shown are for information only and do not need to be investigated. The values reported for height and diameter show a smaller spread than the test method tolerances might suggest adding confidence that high quality samples were produced. Although a few failed to submit some intermediate results overall the performance by participating laboratories with respect to the intermediate results was good. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 12 of 39

13 This page has been left blank for formatting purposes. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 13 of 39

14 4.1 Sample A - Compressive Strength: Z - Scores Code Test A Result MPa Z Score Code Test A Result MPa Z Score Y E T9 NR E N Q J R C A N B S K M E P T S F Z E U Q6 NR G M Y L M W W8 NR G # Z Q E D F8 NR V5 NR L W Q J C Z Statistic Value Number of results 39 Median Median MU 0.32 First Quartile Third Quartile IQR 2.15 Normalised IQR 1.59 CV (%) 3.6 Minimum (39.2) Maximum (48.0) Range 6.56 (8.8) Note: A # indicates an outlier where the z-score obtained is either greater then 3 or less than -3. Codes for all participates are shown. The results column shows NR for those participants that did not submit a result for this test. Minimum, Maximum and Range are calculated with outliers excluded, those in brackets include outliers. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 14 of 39

15 4.1 Sample A - Compressive Strength: Z - Score Graph M6 K3 Y2 W4 W2 C5 U5 R9 Q5 S7 Z2 E2 E7 P8 T3 Q9 Q8 M4 Y6 E6 B6 E8 Z8 L3 J2 M5 D2 A7 N4 C6 F6 G4 Z4 E4 N2 S4 J8 L2 G Z - Score Review Weak Consensus Strong Consensus Weak Consensus Review Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 15 of 39

16 4.2 Sample A - Mass per Unit Volume : Z - Scores Code Test A Result Z Score Code kg/m 3 Test A Result kg/m 3 Z Score Y E T9 NR E N Q J R C A N B S K M E P T # S F Z E U Q6 NR G M Y L M W W8 NR G Z Q E D F8 NR V5 NR L2 NR W Q J C Z Statistic Value Number of results 38 Median 2376 Median MU 3.6 First Quartile 2361 Third Quartile 2385 IQR 24.3 Normalised IQR 18.0 CV (%) 0.8 Minimum 2340 (2320) Maximum 2402 (2402) Range 62 (82) Note: A # indicates an outlier where the z-score obtained is either greater then 3 or less than -3. Codes for all participates are shown. The results column shows NR for those participants that did not submit a result for this test. Minimum, Maximum and Range are calculated with outliers excluded, those in brackets include outliers. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 16 of 39

17 4.2 Sample A - Mass per Unit Volume : Z - Score Graph N4 K3 S7 M6 E2 E6 E7 Y6 G5 Q9 Y2 E4 L3 C6 Q5 W4 J2 U5 F6 E8 M5 Q8 M4 J8 S4 W2 Z8 Z2 B6 R9 C5 P8 Z4 N2 D2 G4 A7 T Z - Score Review Weak Consensus Strong Consensus Weak Consensus Review Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 17 of 39

18 4.3 Sample B - Compressive Strength: Z - Scores Code Test A Result MPa Z Score Code Test A Result MPa Z Score Y E T9 NR E N Q J R C A N B # S K M E P T S F Z E U Q6 NR G M Y L M W W8 NR G # Z # Q E D F8 NR V5 NR L2 NR W Q J C Z Statistic Value Number of results 38 Median 53.5 Median MU 0.44 First Quartile 51.7 Third Quartile 54.6 IQR 2.9 Normalised IQR 2.2 CV (%) 4.1 Minimum 49.5 (41.9) Maximum 57.5 (57.5) Range 8.0 (15.6) Note: A # indicates an outlier where the z-score obtained is either greater then 3 or less than -3. Codes for all participates are shown. The results column shows NR for those participants that did not submit a result for this test. Minimum, Maximum and Range are calculated with outliers excluded, those in brackets include outliers. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 18 of 39

19 4.3 Sample B - Compressive Strength: Z - Score Graph M6 E8 W2 Q8 P8 C5 J2 C6 U5 E7 E2 Q5 Q9 T3 E4 Z8 N4 R9 W4 Y6 M5 Y2 G4 S7 K3 F6 M4 Z4 L3 D2 J8 N2 E6 A7 S4 B6 Z2 G Z - Score Review Weak Consensus Strong Consensus Weak Consensus Review Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 19 of 39

20 4.4 Sample B - Mass per Unit Volume : Z - Scores Code Test A Result Z Score Code kg/m 3 Test A Result kg/m 3 Z Score Y E T9 NR E N Q J R C A N B S K M E P T # S F Z E U Q6 NR G M Y L M W W8 NR G Z Q E # D F8 NR V5 NR L2 NR W Q J C Z Statistic Value Number of results 38 Median 2369 Median MU 2.2 First Quartile 2362 Third Quartile 2377 IQR 14.5 Normalised IQR 10.7 CV (%) 0.5 Minimum 2351 (2300) Maximum 2400 (2403) Range 49 (103) Note: A # indicates an outlier where the z-score obtained is either greater then 3 or less than -3. Codes for all participates are shown. The results column shows NR for those participants that did not submit a result for this test. Minimum, Maximum and Range are calculated with outliers excluded, those in brackets include outliers. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 20 of 39

21 4.4 Sample B - Mass per Unit Volume : Z - Score Graph E7 S7 M5 N4 K3 R9 M4 M6 U5 L3 Z8 Q8 F6 Y2 E2 B6 A7 Q5 C6 J2 Q9 J8 N2 G5 Z2 D2 Y6 E4 E8 E6 C5 W4 P8 S4 W2 G4 Z4 T Z - Score Review Weak Consensus Strong Consensus Weak Consensus Review Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 21 of 39

22 5. Program Details 5.1. Program Design Design The program is held annually. Two concrete cylinders are required to be tested. The cylinders may be matched (same strength) or unmatched in strength (different strengths). The compressive strength also changes from year to year. The test requires a minimum skill level. Adherence to the test method is essential for consistent test results. Participant results are checked where possible. It is expected that the level of experience/skill need to perform these tests will present a reasonable assessment of the overall competency of the tester and industry performance. The program was designed to provide technical feedback regarding performance as well as possible improvements in performance. Other considerations involving the design of the program are detailed below. Role of Proficiency Testing Proficiency testing enables participants to measure competency against others. It is also a measure of staff performance and the equipment used. Next to measurement uncertainty it is the next most useful tool a laboratory has in better understanding the performance of a test. In addition to the statistics, proficiency programs often obtain other information that is not normally available to a laboratory. It allows for a better understanding of the testing and can provide information that can lead to improvements in the testing process or test method. Participant Assessment Assessment of each participant is based on a z-score that is related to the program consensus value (median) and compliance to proficiency program requirements including the correct calculation of results. Reporting of Outliers A Z-Scores Summary is issued soon after the majority of results are received. This gives participants early feedback as to any program outliers. The summary is available on the LabSmart Services website up until the final report is issued. The final report contains detailed technical feedback regarding the performance of tests. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 22 of 39

23 Cylinder Production Concrete Proficiency Testing Program (56) The concrete cylinders used for this program are made specifically for the program under controlled conditions to ensure uniformity in the strength of the cylinders provided. Additional Information Requested This program requested additional information as detailed in Section 6 not usually reported. The additional information is however consistent with the performance of the test and the records the test method requires laboratories to maintain. The additional information is used to interpret participant s performance and assist with providing technical comment including feedback on outliers and possible participant improvement. Participants results were analysed as received regardless of whether there were more or less significant figures than the number requested by the program. Data Checks The determination of outliers is an important task of this proficiency program. A secondary function is to provide feedback that can help those with outliers identify possible areas to investigate as well as assist all participants to improve. This information also helps with identifying any random or systematic errors associated with the test methodology. As observed in other proficiency programs operator errors often creep into the result calculation process. Assessment of participants data was incorporated into this program to ensure data was comparable Sample Preparation Two batches of concrete were prepared. Approximately 70 cylinders were cast of nominal 40 MPa concrete and another 70 of nominal 50 MPa concrete. Cylinders were prepared, cast and cured as per the test standard. Each cylinder was numbered. Eleven cylinders form each batch were selected for homogeneity testing. Samples were selected at evenly spaced intervals through the production process. A total of 22 samples were submitted for homogeneity testing. On removal from the cutting tank each cylinders was wrapped in paper and sealed in a plastic bag. One batch was marked as Sample A and the other Sample B. Samples were drawn at random from each batch to make a pair. Each pair of cylinders was assigned a unique participant code. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 23 of 39

24 5.3. Packaging and Instructions Each pair of cylinders was placed into a sturdy box with bubble wrap. The boxed samples weighed approximately 5 kg. Instructions and a results log sheet were enclosed. (See Appendix B & C) 5.4. Quarantine There were no samples that required additional preparation in order to meet quarantine requirements Despatch Samples were dispatched via courier Homogeneity Testing Samples for homogeneity testing were packed in the same way as those for all participants. The homogeneity samples were tested by an independent NATA accredited laboratory. To approximate the same conditions the same instructions were given to the laboratory performing the homogeneity testing. The overall variability associated with the proficiency samples was considered satisfactory but on the higher side. The magnitude of the results is not acceptable and the NATA accredited facility is currently investigating the issue. Should the results change a revised report will be issued. Any revised report would not change the outcome of this program. Confidence that the samples provided were homogeneous is demonstrated by the very small variation observed in the program for both Sample A and Sample B participant results. A statistical analysis of the homogeneity testing results is provided in table 5.6. Sample A Sample B Compressive Strength MPa Unit Volume kg/m 3 Compressive Strength MPa Unit Volume kg/m 3 Mean Standard Deviation Range Coefficient of Variation (%) Table 5.6 Homogeneity results. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 24 of 39

25 5.7. Participation Forty-four participants from around Australia entered the program. Forty participants returned results. There were four participants whose results were not received in time to be included in this report. Some participants only provided partial results for Sample A and Sample B Statistics Z-Scores were calculated and used to assess the variability of each participant relative to the consensus median. A corresponding z-score graph was produced for each test. See section 4. The use of median and quartiles reduces the effect that outliers have on the statistics and other influences. As a consequence z-scores provide a more realistic or robust method of assessment. Some results were reported by participants to more decimal places than requested as part of the proficiency program and by others to fewer decimal places. In all instances test results have been used as submitted by participants. Checks were undertaken to ensure the data calculated matched that reported by the participant and that the appropriate corrections had been applied if required. If inconsistencies were identified the data was removed but the discrepancy highlighted. A z-score is one way of measuring the degree of consensus with respect to the grouped test results. The z-scores in this report approximates the standard deviation. For each test a z-score graph is shown. Use the graph to visually check statistically how you compare to other participants. The following bar (Figure 5.2) is shown at the bottom of each graph. This helps to quickly visualize where each participant s results falls. Review Weak Consensus Strong Consensus Weak Consensus Review For example: Figure 5.2 Z-score interpretation bar A strong consensus (i.e. agreement) means that your test result is close i.e. within 1 standard deviation of the median. A weak consensus means that your test result is satisfactory and is within 2 standard deviations of the median. If you have obtained a test result that is outside 2 standard deviations then it may be worth reviewing your testing processes to ensure that all aspects are satisfactory. Only those obtaining a z-score approaching 3 (I.e. outside 2.75 range) have been highlighted in the report for review. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 25 of 39

26 If you have obtained a test result that is outside 3 standard deviations then you will need to investigate your testing processes to ensure that all aspects are satisfactory. For further details on the statistics used in this proficiency program can be obtained from LabSmart Services or download the Participant Guide from the LabSmart Services website. Comparing statistics from one proficiency testing program to another The statistics generated from one proficiency program are not usually compared against those from another proficiency testing program. Only very general comparisons may be possible. The reason statistics from one program may not be compared to another is due to the range of variables that differ from one proficiency program to another. These variables include: Type of material selected, The number of participants, Experience of participants, Test methodology variations, Equipment used, Test methods used, Experience of supervisors, Range of organisations involved. It is fair to say that proficiency testing results represent a snap shot of the competency within the industry and hence provides an overview of the industry as a whole. The more participants involved in the program then generally the more representative the overview. Measurement Uncertainty The statistics detailed in this program do not replace the need for laboratories to separately calculated measurement uncertainties associated with each test when required by the client or NATA. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 26 of 39

27 This page has been left blank for formatting purposes. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 27 of 39

28 6.1 Summary of participants results - Sample A Code Sample Received Damage Surface Conditioning Capping Height mm Weight kg Mass per unit volume kg/m3 Maximum Force kn Compressive Strength MPa Failure Date Tested Y2 NR N/A SS Wet Temperate Rubber Conical F 19/11/2014 T9 N2 17/11/2014 Nil Dry Temperate Rubber Normal 19/11/2014 J8 17/11/2014 Nil Dry Temperate Rubber Conical F 19/11/2014 C6 18/11/2014 Good SS Wet Tropical Rubber Conical F 19/11/2014 N4 14/11/2014 N/A Wet Temperate Rubber Conical F 19/11/2014 S4 18/11/2014 NR SS Wet Tropical Sulphur Conical F 19/11/2014 M6 20/11/2014 Nill SS Wet Tropical Rubber Shear F 20/11/2014 P8 21/11/2014 Nil Dry Tropical Rubber Conical F 21/11/2014 S7 21/11/2014 Nil Dry Tropical Rubber Conical F 21/11/2014 Z4 17/11/2014 N/A SS Wet Temperate Rubber Normal 19/11/2014 U5 19/11/2014 NR SS Wet Tropical Gound/Rubbe Conical F 19/11/2014 G4 17/11/2014 Nil Wet Temperate Rubber Normal 19/11/2014 Y6 17/11/2014 Nil SS Wet Tropical Sulphur Conical F 19/11/2014 M4 14/01/2014 Surface voids Wet Temperate Rubber Conical F 19/11/2014 W8 Z2 NR N/A SS Wet Temperate Sulphur Normal 19/11/2014 Q9 17/11/2014 NR SS Wet Tropical Rubber Conical F 19/11/2014 E7 17/11/2014 None Wet Temperate Rubber Conical F 19/11/2014 D2 17/11/2014 very few air bubbles SS Wet Temperate Sulphur Normal 19/11/2014 F8 V5 Concrete Proficiency Testing Program (56) L2 18/11/2014 Nil Wet Tropical Sulphur NR NR NR Diameter mm W4 14/11/2014 NR NR NR Sulphur NR NR 2380 NR 47.0 Normal 19/11/2014 Q8 17/11/2014 SS Wet Tropical Rubber Shear F 19/11/2014 J2 17/11/2014 None SS Wet Tropical Rubber Normal 19/11/2014 C5 28/11/2014 NR Wet Tropical Rubber Conical F 4/12/2014 Note Participants weight results converted to kg where necessary. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 28 of 39

29 Code Sample Received Damage Surface Conditioning Capping Concrete Proficiency Testing Program (56) 6.1 Summary of participants results - Sample A - Continued Height mm Diameter mm Weight kg Mass per unit volume kg/m3 Maximum Force kn Compressive Strength MPa Failure Date Tested Z8 17/11/2014 Nil SS Wet Tropical Rubber Shear F 19/11/2014 E4 NR N/A Wet Tropical Rubber Normal 19/11/2014 E8 17/11/2014 NR Wet Temperate Rubber Normal 26/11/2014 Q5 17/11/2014 Nil Wet Tropical Rubber Conical F 19/11/2014 R9 18/11/2014 Nil SS Wet Tropical Rubber Conical F 19/11/2014 A7 17/11/2014 Nil Dry Temperate Rubber Shear F 19/11/2014 B6 18/11/2014 N/A SS Wet Tropical Rubber Normal 19/11/2014 K3 17/11/2014 No Defects SS Wet Tropical Rubber Normal 19/11/2014 E6 22/11/2014 Nil Wet Tropical Rubber Conical F 24/11/2014 T3 19/11/2014 N/A Wet Tropical Rubber Shear F 20/11/2014 F6 17/11/2014 Nil SS Wet Temperate Rubber Normal 19/11/2014 E2 17/11/2014 Nil SS Wet Tropical Rubber Shear F 19/11/2014 Q6 NR Nil Wet Tropical Sulphur NR 299 NR Conical F 19/11/2014 M5 17/11/2014 N/A Wet Tropical Sulphur Conical F 19/11/2014 L3 14/11/2014 NR SS Wet Temperate Rubber Normal 19/11/2014 W2 NR Nil SS Wet Tropical Rubber Normal 19/11/2014 G5 17/11/2014 Large Bughole SS Wet Tropical End Ground Normal 19/11/2014 Note Participants weight results converted to kg where necessary. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 29 of 39

30 6.2 Summary of participants results - Sample B Code Sample Received Damage Surface Conditioning Capping Height mm Weight kg Mass per unit volume kg/m3 Maximum Force kn Compressive Strength MPa Failure Date Tested Y2 NR N/A SS Wet Temperate Rubber Shear F 19/11/2014 T9 N2 17/11/2014 Nil Dry Temperate Rubber Normal 19/11/2014 J8 17/11/2014 Nil Dry Temperate Rubber Shear F 19/11/2014 C6 18/11/2014 Good SS Wet Tropical Rubber Conical F 19/11/2014 N4 14/11/2014 N/A Wet Temperate Rubber Conical F 19/11/2014 S4 18/11/2014 NR SS Wet Tropical Sulphur Conical F 19/11/2014 M6 20/11/2014 Nill SS Wet Tropical Rubber Conical F 20/11/2014 P8 21/11/2014 Nil Dry Tropical Rubber Conical F 21/11/2014 S7 21/11/2014 Nil Dry Tropical Rubber Conical F 21/11/2014 Z4 17/11/2014 N/A SS Wet Temperate Rubber Normal 19/11/2014 U5 19/11/2014 Nil SS Wet Tropical Gound/Rubber Conical F 19/11/2014 G4 17/11/2014 Nil Wet Temperate Rubber Normal 19/11/2014 Y6 17/11/2014 Nil SS Wet Tropical Sulphur Conical F 19/11/2014 M4 14/11/2014 Surface voids Wet Temperate Rubber Conical F 19/11/2014 W8 Z2 NR N/A SS Wet Temperate Sulphur Shear F 19/11/2014 Q9 17/11/2014 NR SS Wet Tropical Rubber Conical F 19/11/2014 E7 17/11/2014 None Wet Temperate Rubber Conical F 19/11/2014 D2 17/11/2014 Very few air bubbles SS Wet Temperate Sulphur Normal 19/11/2014 F8 V5 Concrete Proficiency Testing Program (56) L2 18/11/2014 Nil Wet Tropical Sulphur NR NR Cap Failure NR Diameter mm W4 14/11/2014 NR NR NR Sulphur NR 2360 NR 53.5 Normal 19/11/2014 Q8 17/11/2014 Air Bubbles top cylinder SS Wet Tropical Rubber Conical F 19/11/2014 J2 17/11/2014 None SS Wet Tropical Rubber Normal 19/11/2014 C5 28/11/2014 NR Wet Tropical Rubber Conical F 4/12/2014 Note Participants weight results converted to kg where necessary. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 30 of 39

31 Code Sample Received Damage Surface Conditioning Capping Concrete Proficiency Testing Program (56) 6.2 Summary of participants results - Sample B - Continued Height mm Diameter mm Weight kg Mass per unit volume kg/m3 Maximum Force kn Compressive Strength MPa Failure Date Tested Z8 17/11/2014 Nil SS Wet Tropical Rubber Normal 19/11/2014 E4 NR N/A Wet Tropical Rubber Shear F 19/11/2014 E8 17/11/2014 NR Wet Temperate Rubber Normal 26/11/2014 Q5 17/01/2014 Nil Wet Tropical Rubber Conical F 19/11/2015 R9 18/11/2014 Nil SS Wet Tropical Rubber Conical F 19/11/2014 A7 17/11/2014 Nil Dry Temperate Rubber Shear F 19/11/2014 B6 18/11/2014 N/A SS Wet Tropical Rubber Normal 19/11/2014 K3 17/11/2014 No Defects SS Wet Tropical Rubber Normal 19/11/2014 E6 22/11/2014 Nil Wet Tropical Rubber Shear F 24/11/2014 T3 19/11/2014 N/A Wet Tropical Rubber Conical F 20/11/2014 F6 17/11/2014 Nil SS Wet Temperate Rubber Normal 19/11/2014 E2 17/11/2014 Nil SS Wet Tropical Rubber Normal 19/11/2014 Q6 NR Nil Wet Tropical Sulphur NR 320 NR Conical F 19/11/2014 M5 17/11/2014 N/A Wet Tropical Sulphur Conical F 19/11/2014 L3 14/11/2014 Top surface rough SS Wet Temperate Rubber Normal 19/11/2014 W2 NR Nil SS Wet Tropical Rubber Normal 19/11/2014 G5 17/11/2014 N/A SS Wet Tropical End Ground Normal 19/11/2014 Note Participants weight results converted to kg where necessary. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 31 of 39

32 Appendix A - NOTES Appendix A-1 to A-4 A # in Appendix A indicates a statistically significant result where the z-score obtained is either greater than 3 or less than -3. This may be useful if it correlates with an unexpected high z score for either the mass per unit volume or compressive strength results. It is not an outlier that has to be investigated. A NR or blank entry occurs where participants did not provide a result. Minimum, Maximum and Range are calculated with outliers included. Appendix A-1: Height AS [Cl (c)] allows the height of the cylinder to be between 195 mm and 205 mm for a 100 mm diameter specimen (200 ± 5 mm). Cylinders may be rejected under AS if height is less than 189 mm, is convex by more than 5 mm or bulges greater than 5 mm etc. Appendix A-2: Average Diameter AS , Clause 6.1.2(a) indicates that the diameter of a sample at any point shall not vary from the average by more than 1 ± mm. The average of two diameter measurements is used in subsequent calculations; hence the average value has been used in calculating these statistics. Appendix A-3: Weight The allowable variation in the dimension of the sample results determines the allowed variation in the volume and is partly responsible for variations in the concrete weights. Other properties of the wet concrete mix and homogeneity of wet mix will have the greater influence on weight. Appendix A-4: Maximum Force The 'Maximum Force' value may be affected by allowable variations in the cylinder dimensions (I.e. does not take into account the effect of the cross sectional area of the sample). Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 32 of 39

33 Code Appendix A-1 Height : Z Scores Test Results (mm) Z Score Test Results (mm) Z Score Code Sample A Sample B Sample A Sample B Sample A Sample B Sample A Sample B 1 Y B T9 NR NR 35 K N E J T C F N E S Q M M P L Z G U # G Y M W8 NR NR Z E D Statistic Sample A 21 F8 NR NR 22 V5 NR NR Number of results L Median W First Quartile Q Third Quartile J IQR C Normalised IQR Z CV (%) E Minimum E Maximum Q Range 4 32 R A IMPORTANT : Please Read Appendix A: NOTES Sample B Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 33 of 39

34 Code Appendix A-2 Average Diameter : Z Scores Test Results (mm) Z-score Test Results (mm) Z-score Code Sample A Sample B Sample A Sample B Sample A Sample B Sample A Sample B 1 Y B T9 NR NR 35 K N E J T # 5.65 # 5 C F N E S Q M M P L Z G U G Y M W8 NR NR Z E # D Statistic Sample A 21 F8 NR NR 22 V5 NR NR Number of results L Median W4 NR First Quartile Q Third Quartile J # IQR C Normalised IQR Z CV (%) E Minimum E Maximum Q Range R A # IMPORTANT : Please read Appendix A: NOTES Sample B Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 34 of 39

35 Code Appendix A-3 Weight : Z Scores Test Results (kg) Z-score Test Results (kg) Z-score Code Sample A Sample B Sample A Sample B Sample A Sample B Sample A Sample B 1 Y B T9 NR NR 35 K N E J T C F # 3.88 # 6 N E S Q M M P L Z G # 12 U # G Y M W8 NR NR Z E D Statistic Sample A 21 F8 NR NR 22 V5 NR NR Number of results L Median W4 NR NR First Quartile Q Third Quartile J # IQR C Normalised IQR Z # CV (%) E Minimum E Maximum Q Range R A IMPORTANT : Please read Appendix A: NOTES Sample B Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 35 of 39

36 Code Appendix A-4 Maximum Force : Z Scores Test Results (kn) Z-score Test Results (kn) Z-score Code Sample A Sample B Sample A Sample B Sample A Sample B Sample A Sample B 1 Y B T9 NR NR 35 K N E J T C F N E S Q # # 8 M M P L Z G # # 12 U G Y M W8 NR NR Z # 19 E D Statistic Sample A 21 F8 NR NR 22 V5 NR NR Number of results L Median W4 NR NR First Quartile Q Third Quartile J IQR C Normalised IQR Z CV (%) E Minimum E Maximum Q Range R A IMPORTANT : Please read Appendix A: NOTES Sample B Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 36 of 39

37 Appendix B LabSmart Services Concrete Compression Proficiency Program 2014 (56) INSTRUCTIONS FOR TESTER 1. Do not open the plastic bags until Store at room temperature away from fluctuating temperatures and sunlight. 2. Please read these instructions carefully. 3. Please check that the package you have received contains the following: Results Log Two nominal 100 mm Ø by 200 mm concrete cylinders sealed in plastic bags marked Sample A and Sample B. 4. Inspect packaging on arrival for damage or leakage. Contact LabSmart Services if box is wet or damaged or anything is missing (Phone ) 5. It is strongly recommended that participants follow AS 1012, Method 9 when testing the concrete cylinders but an alternative equivalent method may also be used. 6. On 19 th November remove each cylinder from the plastic bag. Remove newspaper covering. Inspect each cylinder and record its condition on the proficiency testing results log sheet (AS 1012, clause 4.1 (a) to (h)). If cylinders show any chipping or damage please contact LabSmart Services before testing. Air bubbles are expected. 7. Within 10 minutes of opening the plastic bag immerse each concrete cylinder into the curing tank. Allow the cylinders to pre-condition for at least three hours prior to capping and testing by full immersion in water at 23 ± 2 o C temperate zone or 27 ± 2 o C tropical zone. 8. Follow AS 1012, Method 9. Test both cylinders within 15 minutes of each other. 9. Record all information and calculations as per AS 1012, Method 9 on the proficiency testing results log sheet but to the accuracy shown on the results log sheet. 10. Ensure to have the Laboratory Supervisor check & approve then sign the log sheet. 11. Please fax or the Results Log to LabSmart Services by 24 November Fax: (03) OR petery@labsmartservices.com.au 12. Please retain the completed Results Log as this contains your participation code that will identify your results in the technical report covering the proficiency testing program. It is also recommended that a copy of completed worksheets be kept with the results log in your proficiency file. 13. Have a query? Contact Peter at LabSmart Services. Phone Thank you for participating in this proficiency testing program. Copyright: : LabSmart Services Pty Ltd Report V1 - February 2015 Page 37 of 39