Precision Estimates for AASHTO Test Methods T 186, T 154, and T 22, Determined Using CCRL Proficiency Sample Data (2009)

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ACKNOWLEDGMENT This work was sponsored by the American Association of State Highway and Transportation Officials (AASHTO), in cooperation with the Federal Highway Administration, and was conducted in the National Cooperative Highway Research Program (NCHRP), which is administered by the Transportation Research Board (TRB) of the National Academies. COPYRIGHT PERMISSION Authors herein are responsible for the authenticity of their materials and for obtaining written permissions from publishers or persons who own the copyright to any previously published or copyrighted material used herein. Cooperative Research Programs (CRP) grants permission to reproduce material in this publication for classroom and not-for-profit purposes. Permission is given with the understanding that none of the material will be used to imply TRB, AASHTO, FAA, FHWA, FMCSA, FTA, Transit Development Corporation, or AOC endorsement of a particular product, method, or practice. It is expected that those reproducing the material in this document for educational and not-for-profit uses will give appropriate acknowledgment of the source of any reprinted or reproduced material. For other uses of the material, request permission from CRP. DISCLAIMER The opinion and conclusions expressed or implied in the report are those of the research agency. They are not necessarily those of the TRB, the National Research Council, AASHTO, or the U.S. Government. This report has not been edited by TRB.

NCHRP Web-Only Document 140: Precision Estimates for AASHTO Test Methods T 186, T 154, and T 22 iii TABLE OF CONTENT LIST OF TABLES ............................................................................................................ v  ACKNOWLEDGMENTS ............................................................................................... vi  CHAPTER 1. INTRODUCTION AND RESEARCH APPROACH ........................... 1  1.1  INTRODUCTION ........................................................................................... 1  1.1.1  Problem Statement ............................................................................... 2  1.1.2  Research Objective .............................................................................. 2  1.2  SCOPE OF STUDY ......................................................................................... 2  1.3  PROFICIENCY SAMPLES USED IN STUDY .............................................. 2  CHAPTER 2. RESULTS OF ANALYSIS AND ESTIMATES OF PRECISION ...... 4  2.1  TEST DATA .................................................................................................... 4  2.2  ANALYSIS OF THE DATA ........................................................................... 4  2.2.1  Early Stiffening (False Set), T 186 ...................................................... 4  2.2.2  Gillmore Time of Setting, T 154 ......................................................... 5  2.2.2.1  Initial Time of Setting ........................................................... 5  2.2.2.2  Final Time of Setting ............................................................ 6  2.2.3  Compressive Strength, T 22 ................................................................ 6  2.3  COMPARISON OF CURRENT AND DEVELOPED PRECISONS .............. 7  2.3.1  Early Stiffening (False Set), T 186 ...................................................... 7  2.3.2  Gillmore Time of Setting, T 154 ......................................................... 7  2.3.3  Compressive Strength, T 22 ................................................................ 8  CHAPTER 3. CONCLUSIONS AND RECOMMENDATIONS ................................. 9  3.1  COMMENTARY ............................................................................................ 9  3.2  CONCLUSION ................................................................................................ 9  3.3  RECOMMENDATIONS ................................................................................. 9  3.4  PRECISION STATEMENT FOR AASHTO T 186 EARLY STIFFENING OF HYDRAULIC CEMENT (PASTE METHOD) ....................................... 10  3.5  PRECISION STATEMENT FOR AASHTO T 154 TIME OF SETTING OF HYDRAULIC CEMENT PASTE BY GILLMORE NEEDLES ............. 11 

NCHRP Web-Only Document 140: Precision Estimates for AASHTO Test Methods T 186, T 154, and T 22 iv 3.6  PRECISION STATEMENT FOR AASHTO T 22 COMPRESSIVE STRENGTH OF CYLINDRICAL CONCRETE SPECIMENS .................... 12  REFERENCES ………………………………………………………………………13  APPENDIX A:  EARLY STIFFENING (FALSE SET) ........................................... 14  APPENDIX B:  GILLMORE INITIAL TIME OF SETTING ............................... 21  APPENDIX C:  GILLMORE FINAL TIME OF SETTING .................................. 28  APPENDIX D:  COMPRESSIVE STRENGTH ....................................................... 35 

NCHRP Web-Only Document 140: Precision Estimates for AASHTO Test Methods T 186, T 154, and T 22 v LIST OF TABLES Table 1-1- Sample Designation, Cement Type, and Date of Final Reports of Proficiency Samples used for AASHTO T 186 (ASTM C 451) and AASHTO T 154 (C 266) Data Mining ................................................................................................................ 3  Table 1-2- Sample Designation, Sample Size, and Date of Final Report of Proficiency Samples used for AASHTO T 22 (ASTM C 39) Data Mining ............................... 3  Table 2-1- Summary Table for % Early Stiffening of Hydraulic Cement, T 186 ................... 4  Table 2-2- Summary Table for Initial Time of Setting, T 154 ................................................... 5  Table 2-3- Summary Table for Final Time of Setting, T 154 .................................................... 6  Table 2-4- Summary Table for 7-Day Compressive Strength, T 22 ......................................... 6  Table 2-5- Comparison of the Proposed and Existing Precision Estimates for T 186 ............. 7  Table 2-6- Comparison of Proposed and Existing Precision Estimates for T 154 ................... 7  Table 2-7-Comparison of the Proposed and Existing Precision Estimates for T 22 ................ 8 

NCHRP Web-Only Document 140: Precision Estimates for AASHTO Test Methods T 186, T 154, and T 22 vi ACKNOWLEDGMENTS The research reported herein was performed under NCHRP Project 9-26A by the AASHTO Materials Reference Laboratory (AMRL). Dr. Haleh Azari and Mr. Robert Lutz were co-principal investigators on the study. Mr. Robin Haupt the CCRL Proficiency Program Manager played supporting role and provided valuable comments in the study.