NCHRP Report 409 - Quality Control and Acceptance of Superpave-Designed Hot Mix Asphalt

218 Pages·1998·3.89 MB·English

N A T I O N A L C O O P E R A T I V E H I G H W A Y R E S E A R C H P R O G R A M
NCHRP
Report 409
Quality Control and Acceptance of
Superpave-Designed Hot Mix Asphalt
Transportation Research Board
National Research Council
TRANSPORTATION RESEARCH BOARD EXECUTIVE COMMITTEE 1998
OFFICERS
Chairwoman: Sharon D. Banks, General Manager, AC Transit
Vice Chairman: Wayne Shackelford, Commissioner, Georgia Department of Transportation
Executive Director: Robert E. Skinner, Jr., Transportation Research Board
MEMBERS
THOMAS F. BARRY, JR., Secretary of Transportation, Florida Department of Transportation
BRIAN J.L. BERRY, Lloyd Viel Berkner Regental Professor, Bruton Center for Development Studies, University of Texas at Dallas
SARAH C. CAMPBELL,President, TransManagement, Inc., Washington, DC
E. DEAN CARLSON, Secretary, Kansas Department of Transportation
JOANNE F. CASEY, President, Intermodal Association of North America, Greenbelt, MD
JOHN W. FISHER, Director, ATLSS Engineering Research Center, Lehigh University
GORMAN GILBERT, Director, Institute for Transportation Research and Education, North Carolina State University
DELON HAMPTON, Chair and CEO, Delon Hampton & Associates, Washington, DC
LESTER A. HOEL, Hamilton Professor, Civil Engineering, University of Virginia
JAMES L. LAMMIE, Director, Parsons Brinckerhoff, Inc., New York, NY
THOMAS F. LARWIN, General Manager, San Diego Metropolitan Transit Development Board
BRADLEY L. MALLORY, Secretary of Transportation, Pennsylvania Department of Transportation
JEFFREY J. McCAIG, President and CEO, Trimac Corporation, Calgary, Alberta, Canada
JOSEPH A. MICKES, Chief Engineer, Missouri Department of Transportation
MARSHALL W. MOORE, Director, North Dakota Department of Transportation
ANDREA RINIKER, Executive Director, Port of Tacoma
JOHN M. SAMUELS, VP-Operations Planning & Budget, Norfolk Southern Corporation, Norfolk, VA
LES STERMAN, Executive Director, East-West Gateway Coordinating Council, St. Louis, MO
JAMES W. VANLOBEN SELS, Director, CALTRANS(Past Chair, 1996)
MARTIN WACHS, Director, University of California Transportation Center, University of California at Berkeley
DAVID L. WINSTEAD, Secretary, Maryland Department of Transportation
DAVID N. WORMLEY, Dean of Engineering, Pennsylvania State University (Past Chair, 1997)
MIKE ACOTT, President, National Asphalt Pavement Association (ex officio)
JOE N. BALLARD, Chief of Engineers and Commander, U.S. Army Corps of Engineers (ex officio)
ANDREW H. CARD, JR., President and CEO, American Automobile Manufacturers Association (ex officio)
KELLEY S. COYNER, Acting Administrator, Research and Special Programs, U.S. Department of Transportation (ex officio)
MORTIMER L. DOWNEY, Deputy Secretary, Office of the Secretary, U.S. Department of Transportation (ex officio)
FRANCIS B. FRANCOIS, Executive Director, American Association of State Highway and Transportation Officials (ex officio)
DAVID GARDINER, Assistant Administrator, U.S. Environmental Protection Agency (ex officio)
JANE F. GARVEY, Federal Aviation Administrator, U.S. Department of Transportation (ex officio)
JOHN E. GRAYKOWSKI, Acting Maritime Administrator, U.S. Department of Transportation (ex officio)
ROBERT A. KNISELY, Deputy Director, Bureau of Transportation Statistics, U.S. Department of Transportation (ex officio)
GORDON J. LINTON, Federal Transit Administrator, U.S. Department of Transportation (ex officio)
RICARDO MARTINEZ, National Highway Traffic Safety Administrator, U.S. Department of Transportation (ex officio)
WALTER B. McCORMICK, President and CEO, American Trucking Associations, Inc. (ex officio)
WILLIAM W. MILLAR, President, American Public Transit Association (ex officio)
JOLENE M. MOLITORIS, Federal Railroad Administrator, U.S. Department of Transportation (ex officio)
KAREN BORLAUG PHILLIPS, Senior Vice President, Association of American Railroads (ex officio)
VALENTIN J. RIVA, President, American Concrete Pavement Association
GEORGE D. WARRINGTON, Acting President and CEO, National Railroad Passenger Corporation (ex officio)
KENNETH R. WYKLE, Federal Highway Administrator, U.S. Department of Transportation (ex officio)
NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM
Transportation Research Board Executive Committee Subcommittee for NCHRP
SHARON BANKS, AC Transit (Chairwoman) WAYNE SHACKELFORD, Georgia Department of Transportation
FRANCIS B. FRANCOIS, American Association of State Highway and ROBERT E. SKINNER, JR., Transportation Research Board
Transportation Officials DAVID N. WORMLEY, Pennsylvania State University
LESTER A. HOEL, University of Virginia KENNETH R. WYKLE, Federal Highway Administration
Project Panel D9-7 Field of Materials and Construction Area of Bituminous Materials
W. M. LACKEY, Kansas Department of Transportation(Chair) CHARLES F. POTTS, APAC, Inc., Atlanta, GA
TIMOTHY B. ASCHENBRENER, Colorado Department of Transportation B. F. TEMPLETON, Texas Department of Transportation
WAYNE BRULE, New York State Department of Transportation JAMES M. WARREN, Asphalt Contractors Association of Florida, Inc.
JOHN D’ANGELO, Federal Highway Administration PETER A. KOPAC, FHWALiaison Representative
GAIL JENSEN, Mathy Construction, Onalasha, WI HALEEM TAHIR, AASHTO Liaison Representative
GALE C. PAGE, Florida Department of Transportation FRED HEJL, TRB Liaison Representative
Program Staff
ROBERT J. REILLY, Director, Cooperative Research Programs RONALD D. McCREADY, Senior Program Officer
CRAWFORD F. JENCKS, Manager, NCHRP KENNETH S. OPIELA, Senior Program Officer
DAVID B. BEAL, Senior Program Officer EILEEN P. DELANEY, Managing Editor
LLOYD R. CROWTHER, Senior Program Officer HELEN CHIN, Assistant Editor
B. RAY DERR, Senior Program Officer JAMIE FEAR, Assistant Editor
AMIR N. HANNA, Senior Program Officer HILARY FREER, Assistant Editor
EDWARD T. HARRIGAN, Senior Program Officer
N A T I O N A L C O O P E R A T I V E H I G H W A Y R E S E A R C H P R O G R A M
Report 409
Quality Control and Acceptance of
Superpave-Designed Hot Mix Asphalt
RONALD J. COMINSKY
and
BRIAN M. KILLINGSWORTH
Brent Rauhut Engineering Inc.
Austin, TX
R. MICHAEL ANDERSON
The Asphalt Institute
Lexington, KY
DAVID A. ANDERSON
Pennsylvania Transportation Institute
Pennsylvania State University
WILLIAM W. CROCKFORD
Consultant
College Station, TX
Subject Areas
Materials and Construction
Research Sponsored by the American Association of State
Highway and Transportation Officials in Cooperation with the
Federal Highway Administration
TRANSPORTATION RESEARCH BOARD
NATIONAL RESEARCH COUNCIL
NATIONAL ACADEMY PRESS
Washington, D.C. 1998
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FOREWORD This report presents a plan, in the form of a draft AASHTO standard practice, for qual-
ity control (QC) and quality acceptance (QA) of field production, placement, and com-
By Staff paction of hot mix asphalt (HMA) prepared in conformance with Superpave materials spec-
Transportation Research ifications and mix designs. It will be of particular interest to materials engineers in state
Board highway agencies and to those agency and contractor personnel responsible for control and
acceptance of HMA paving projects. The report also contains the detailed research results
supporting the development of the QC/QA plan, including experimental data obtained dur-
ing the construction of pavement projects using Superpave mix designs across the United
States.
A principal product of the Strategic Highway Research Program (SHRP) is the Super-
pave performance-based mix design and analysis method. This method incorporates new,
performance-based material specifications, test methods, and design and analysis proce-
dures for HMA. Interest in the Superpave method has grown rapidly since the conclusion
of SHRP in 1993. The Superpave Lead State Team of the AASHTO Task Force on the
Implementation of SHRP reported that in 1996, 28 states incorporated both binder and mix
specifications in awarding 95 Superpave projects. Nationally, these projects represented
approximately 1 percent of total projects and 2 percent of total tonnage. For 1997, projected
figures indicated that the number of states using Superpave would increase to greater than
40, while planned projects totaled in excess of 300. However, to realize the maximum ben-
efit of improved performance possible through the Superpave method, state highway agen-
cies must ensure that the production, placement, and compaction of HMA in field projects
are controlled to maintain compliance with the Superpave specifications and mix design.
Under NCHRP Project 9-7 “Field Procedures and Equipment to Implement SHRP
Asphalt Specifications” Brent Rauhut Engineering Inc. was assigned the tasks of (1) estab-
lishing comprehensive procedures and, if required, developing equipment for QC/QA of
field production, placement, and compaction to ensure that as-placed HMA conforms with
the Superpave mix design and (2) preparing a training program for qualifying technicians
to accomplish these QC/QA procedures.
The research team reviewed relevant domestic and foreign literature on established and
innovative process control methods in the HMA industry as well as the wider manufactur-
ing sector; carried out field QC/QA operations and conducted extensive laboratory testing
on field- and laboratory-compacted specimens from 15 pavement projects constructed in
1994, 1995, and 1996; evaluated a variety of test methods and equipment for contractor con-
trol of field operations with Superpave-designed HMA; and developed a prototype field
shear test (FST) device to measure key HMA performance properties during pavement
construction.
This NCHRP report presents several products expected to facilitate the wider imple-
mentation of the Superpave mix design method: a QC/QA plan, including tolerances for
key materials and volumetric mix properties, for field production and lay down of HMA
produced in accordance with Superpave material specifications and mix designs method
(Chapter 2); guidelines for adjustment of production and placement of HMA to maintain
conformance with Superpave specifications and mix designs (Chapter 3); a training pro-
gram (available in the form of a Microsoft Powerpoint presentation) for qualifying techni-
cians to use the procedures set forth in the QC/QA plan (Chapter 4); and equipment require-
ments, test procedures, and data analysis techniques for use of the Superpave gyratory
compactor as the principal tool in QC/QA operations, and for the FST device and the rapid
triaxial test that with further development may complement the gyratory compactor in such
operations (Chapter 5).
The QC/QA plan presented in Chapter 2 establishes minimum requirements and activ-
ities for a contractor’s QC system related to Superpave mix design, production, placement,
and compaction. These requirements include a listing of the inspections and tests necessary
to substantiate material and product conformance to the Superpave mix design. The primary
method of field QC employs the Superpave gyratory compactor and evaluation of the vol-
umetric properties of the mix.
The plan also establishes requirements for a state highway agency’s assessment and
acceptance of a project incorporating Superpave-designed HMA. This plan, coupled with
the contractor’s QC plan, provides the necessary quality assurance for control, verification,
and acceptance of the project.
CONTENTS 1 CHAPTER 1 Quality Control and Acceptance of Superpave-Designed Hot Mix
Asphalt
1.1 Introduction, 1
3 CHAPTER 2 QC/QA Plan for Production and Lay Down of Superpave HMA
2.1 Scope, 3
2.1.1 Functions and Responsibilities, 3
2.1.2 QC System, 3
2.2 Superpave Performance-Graded Asphalt Binder (PGAB) Certification, 4
2.2.1 PGAB QC, 4
2.2.2 AASHTO PP26-96 Standard, 4
2.3 Superpave Mix Design and Production, 4
2.3.1 Laboratory Trial Mix Formula (LTMF) and HMA Plant Laboratory
Verification, 4
2.3.2 Field Verification and Adjustment to the LTMF, 4
2.3.3 Establishment of Compaction Rolling Pattern (Control Strip), 5
2.4 Sampling and Testing, 6
2.5 QC Activities, 6
2.5.1 Plant-Produced Superpave Mix QC, 6
2.5.2 QC of In-Place Compaction, 7
2.6 Nonconforming Materials, 7
2.7 SHA Inspection at Subcontractor or Supplier Facilities, 7
2.8 Superpave Quality Acceptance Plan, 7
2.8.1 Scope, 8
2.8.2 Acceptance Plan Approach for Superpave-Designed HMA, 8
2.8.3 Superpave PGAB Certification, 8
2.8.4 Superpave Specifications and Mix Verifications, 10
2.8.5 Acceptance Criteria for Superpave-Designed HMA, 12
2.8.6 Pavement Compaction, 13
14 ANNEX I Conformal Index Approach
16 ANNEX II Stratified Random Sampling Approach
21 ANNEX III Statistical Control Charts
24 CHAPTER 3 Guidelines for Adjusting the Production and Placement of
Superpave-Designed HMA
3.1 Noncomplying Gradation Tests, 24
3.1.1 Incoming Aggregates, 24
3.1.2 Combined Hot Bin Aggregate, 24
3.2 Noncomplying HMA Test Results, 24
3.2.1 Air Voids Above or Below Specifications, 24
3.2.2 VMA, 25
3.2.3 Increasing VMA, 25
3.2.4 Decreasing VMA, 25
3.2.5 VFA, 25
3.3 Noncomplying Field Density Tests, 25
3.4 Miscellaneous Irregularities in Pavement, 26
3.4.1 Checking and Cracking of Newly Constructed Pavement, 26
3.4.2 Shoving of the Compacted Pavement, 26
3.4.3 Raveling in the Finished Pavement, 26
3.4.4 Tender Pavements, 26
27 CHAPTER 4 A Training Course to Implement QC/QA Plans for Production
and Placement of Superpave-Designed HMA
4.1 Introduction, 27
4.2 Overview of Training Course, 27
58 CHAPTER 5 Equipment to Support Superpave QC/QA Plan
5.1 Introduction, 58
5.2 Gyratory Compaction Control, 58
5.2.1 Volumetric Property Control, 58
5.2.2 Gyratory Compaction, 59
5.2.3 Field QC Using the SGC, 60
5.3 Performance-Based Property Control, 62
5.3.1 FST Device, 63
5.3.2 Rapid Triaxial Testing Approach to Flexible Pavement QC/QA, 67
77 CHAPTER 6 Summary of the Research Project
6.1 Introduction, 77
6.2 Objectives and Organization of the Research, 77
6.3 Conduct of the Research, 78
6.3.1 Phase I: Literature Surveys, 78
6.3.2 Phase II: Experiment Design and Field Experiments, 90
110 APPENDIX A Additional Training Modules
110 APPENDIX B Field Shear Test Procedure in AASHTO Draft Fomat
110 APPENDIX C Rapid Triaxial Test Procedure in AASHTO Draft Format
111 APPENDIX D Summary of Information for Projects Constructed in 1994
149 APPENDIX E Summary of Information for Projects Constructed in 1995
177 APPENDIX F Summary of Information for Verification of Version 2.0 QC/QA
Plan
178 APPENDIX G Comparison of Quality Control and Acceptance Tests
184 APPENDIX H Quality Control Testing of Asphalt Binders
185 APPENDIX I Sensitivity of SUPERPAVE Mixture Tests to Changes
in Mixture Components
AUTHOR ACKNOWLEDGMENTS
The research effort reported herein was performed under portation Institute), and Dr. Bill Crockford (formerly of the Texas
NCHRP Project 9-7 by Brent Rauhut Engineering Inc., which Transportation Institute, now a representative of Industrial Process
served as the prime contractor. Subcontractors for the project Controls through TSL Services and Equipment).
included the Pennsylvania Transportation Institute, the Asphalt The authors also acknowledge the valuable assistance of Ms. Terhi
Institute, Advanced Asphalt Technologies, the Texas Transporta- Pellinen (formerly of Advanced Asphalt Technologies, now with
tion Institute, and Law Engineering. In addition, Industrial Process the University of Maryland) for her efforts. Three consultants also
Controls generously provided test equipment and staff involvement provided valuable assistance: Dr. Matthew Witczak, Mr. Garland
at no cost to the project. Steele, and Mr. James Scherocman. Mr. Barry Tritt (Industrial
Mr. Ronald J. Cominsky, formerly of BRE Inc., now Executive Process Controls) is also acknowledged for providing valuable
Director of the Pennsylvania Asphalt Pavement Association, information and test data to the project from test equipment devel-
served as the Principal Investigator for the project and primary oped by IPC.
author of this report. Valuable assistance in conducting the project The authors also acknowledge the cooperation of several State
and authoring the report was provided by Mr. Brian M. Killings- Highway Agencies and contractors who participated in the produc-
worth of BRE Inc. Others who contributed to this report include tion and construction of field test sites. The States that participated
Dr. David A. Anderson (Pennsylvania Transportation Institute), include Kentucky, Virginia, Florida, Texas, Mississippi, Alabama,
Mr. R. Michael Anderson (Asphalt Institute), Mr. Vince Aurilio Georgia, Kansas, Maryland, and Louisiana. Material was also sam-
(Advanced Asphalt Technologies), Dr. Thomas W. Kennedy (Uni- pled and tested from test sections constructed at WesTrack in
versity of Texas at Austin), Dr. Robert L. Lytton (Texas Trans- Nevada.
1
CHAPTER 1
QUALITY CONTROL AND ACCEPTANCE OF SUPERPAVE-DESIGNED
HOT MIX ASPHALT
1.1 INTRODUCTION NCHRP Project 9-7 had two key objectives:
Interest in the Superpave performance-based mix design • To establish comprehensive procedures and, if required,
and analysis system, developed through the asphalt research develop equipment for QC/QA at the asphalt plant and lay
program of the Strategic Highway Research Program (SHRP), down site to ensure that hot mix asphalt (HMA) meets the
is rapidly growing throughout the nation. AASHTO member Superpave performance-based specifications and
departments are actively gearing up for Superpave imple- • To develop a framework for a training program for qual-
mentation. The AASHTO Task Force on SHRP Implementa- ifying technicians to accomplish these QC/QA proce-
tion has targeted SHRP’s asphalt products as one of its pri- dures.
orities. Members of the AASHTO Highway Subcommittee
on Materials are evaluating more than 20 specific products in After a review of the SHRP asphalt research program results
the asphalt area. A pooled-fund study has assisted the states and discussion with the NCHRP Project 9-7 panel, a decision
was made to consider only permanent deformation as a dis-
to obtain the necessary laboratory test equipment. The Fed-
tress factor. Permanent deformation is a short-term phenome-
eral Highway Administration (FHWA) has established five
non that can be evaluated by QC/QA field testing. Pavement
Superpave Regional Centers nationally to assist state highway
fatigue is a long-term phenomenon that is generally addressed
agencies (SHAs) with Superpave implementation. Industry
through pavement layer thickness determination during the
must be involved, however, to fully implement SHRP’s rec-
pavement design process. Low-temperature cracking is ad-
ommendations and will need the knowledge and tools to com-
dressed during the Superpave mix design process by the selec-
ply with the new requirements. To that end, user-producer
tion of the appropriate performance grade of asphalt binder.
groups are operating on a regional basis, involving SHAs,
This report presents QC/QA procedures developed on the
contractors, and materials manufacturers and suppliers. Infor-
basis of experimental data obtained from 14 field paving proj-
mation presented to these groups, initially by SHRP and now
ects during the course of the project. The report assumes a
by the FHWA, has built wide-ranging support for adoption of
familiarity with the Superpave mix design procedures includ-
this new system of material specifications, test methods and
ing the use of the Superpave gyratory compactor (SGC).1
equipment, design and analysis practices, and software.
Although the current focus of the SHAs is on the Super-
Such significant improvements in asphalt binders, test
pave volumetric mix design method (originally termed
equipment and procedures, analysis of test results, and spec-
Superpave level 1), Project 9-7 also considered the original
ifications should provide a substantially greater level of per-
Superpave level-2and Superpave level-3 design procedures
formance from paving mixes designed with the Superpave
(now termed abbreviated and full mix analyses) recom-
system. However, to realize these improvements, SHAs must
mended by SHRP. Further, in this report the QC function is
ensure that the production, placement, and compaction of
assigned specifically to the paving Contractor and the QA
paving mixes in field projects are controlled to maintain com-
function is assigned solely to the SHA.
pliance with the specifications.
The report is organized in two parts. Part I (Chapters 2
A general approach to field control procedures was devel-
through 6) provides specific details of the products delivered
oped under SHRP to assist field technicians in adjusting mix
by the research project and is intended for the practitioner
design and monitoring production. The need was identified
and the user. Part I includes the following:
for additional research to specifically provide SHAs and
paving contractors with appropriate quality control and qual- • A QC/QA plan for field production and lay down of
ity assurance (QC/QA) procedures for the field implementa- HMA produced in accordance with Superpave material
tion of the Superpave material specifications and mix specifications and mix design method (Chapter 2);
designs. NCHRP Project 9-7, “Field Procedures and Equip-
ment to Implement SHRP Asphalt Specifications,” was initi-
1AASHTO TP4, Standard Method for Preparing and Determining the Density of
ated to satisfy this requirement. HMA Specimens by Means of the SHRP Gyratory Compactor.
2
• Guidelines for adjustment of production and placement • Test procedures for the field QC devices developed dur-
of Superpave-designed HMA (Chapter 3); ing the project (Appendices B and C);
• A training program for qualifying technicians to use the • The Stage I research approach: Superpave mix designs for
procedures set forth in the QC/QA plan (Chapter 4); six experimental construction projects conducted in 1994;
• A description of two field-testing devices that support QC data for the six projects; statistical analyses; and con-
the SGC for QC practices and provisional test proce- clusions for the Version 1 QC/QA plan (Appendix D);
dures and data analysis for their use (Chapter 5); and • The Stage II research approach: Superpave mix designs
• A summary of the research results of NCHRP Project for seven experimental construction projects in 1995; QC
9-7 and the conclusions drawn from the results that form data for the seven projects; statistical analyses; and con-
the basis for the QC/QA practices and suggested guide- clusions for the Version 2 QC/QA plan (Appendix E);
lines for mix and placement adjustments (Chapter 6). • Verification of the Version 2.0 QC/QA plan; Superpave
mix design for a project in Louisiana on which the Ver-
The appendices form Part II of the report. They provide sion 2.0 plan was used; statistical control charts; com-
complete experimental details and results upon which the paction data, and statistical analyses (Appendix F);
products presented in Chapters 2 through 5 are based. The • Dispute resolution: Statistically based guidelines for
appendices include the following: comparison of QC and QA data adopted by AASHTO
(Appendix G);
• Additional training information that can be used for • Shear displacement rheometer (SDR) (Appendix H);
assisting in the implementation of Superpave activities and
(Appendix A); • Gyratory sensitivity (Appendix I).