TRB Superpave Abstracts 2001

TRB Superpave Abstracts 2001

80th Transportation Research Board Annual Meeting

January 7- 11, 2001

Washington, D. C.

Table of Contents

Washington State Dot Superpave Implementation
Mechanistic Analysis of Asphalt Pavements Using Superpave Shear Tester and Hamburg Wheel-Tracking Device
Impact of Gradation Relative to the Superpave Restricted Zone on HMA Performance
Comparison of the Engineering Characteristics of Asphalt Mixes To Field Data and Pavement Performance
Effect of Superpave Gyratory Compactor Type on Compacted Hot Mix Asphalt (HMA) Density
Gradation Effects on HMA Performance
Effect of Aggregate Gradation on Permanent Deformation of Superpave HMA
Forensic Analysis of Arizona™s US-93 Superpave sections
Design, Construction, And Early Performance Of Virginia’s Hot-Mix Asphalt Stabilizer And Modifier Test Sections
Effect of Mix Gradation on Rutting Potential of Dense Graded Asphalt Mixtures
Evaluation of Laboratory Measured Crack Growth Rate for Asphalt Mixtures
Low-temperature Thermal Cracking of Asphalt Binders as Ranked by Strength and Fracture Properties
An Evaluation of Factors Affecting Permeability of Superpave Designed Pavements
Variability of Asphalt Mixtures Tests Using the Superpave Shear Tester Repeated Shear at Constant Height Test
Development of Performance-Based Mix Design for Cold In-Place Recycling of Asphalt Mixtures
Hydraulic Conductivity (Permeability) Of Laboratory Compacted Asphalt Mixtures
Effect of Short Term Oven Aging on Volumetrics And Selection of N-Design
Development of Critical Field Permeability and Pavement Density Values for Coarse-Graded Superpave Pavements
New Jersey’s Superpave Specification: The Next Generation
Development of a Void Pathway Test for Investigating Void Interconnectivity in Compacted Hot-Mix Asphalt Concrete
Asphalt Permeability Testing: Specimen Preparation and Testing Variability
Correlation of Imaging Shape Indices of Fine Aggregate with Asphalt Mixture Performance
A Comparison of Four Brands of Superpave Gyratory Compactors
Field Conditioning of Superpave Asphalt Mixes
A Mathematical Model for Calculating Pavement Temperatures, Comparisons between Calculated and Measured Temperatures
An Evaluation of Field Density Measuring Devices
Discrete Element Modeling of Asphalt Concrete: A Micro-Fabric Approach
Field Tests and Economic Analysis of High-Cure Crumb-Rubber Modified Asphalt Binders in Dense-Graded Mixes
Measurement of Flat and Elongation of Coarse Aggregate Using Digital Image Processing
Microstructure Study of WesTrack Mixes from X-ray Tomography Images
A Statistical Model Of Pavement Rutting In Asphalt Concrete Mixes
Potential of Using Stone Matrix Asphalt (SMA)For Thin Overlays
Repeated Triaxial Testing During Mix Design for Performance Characterization
A Procedure for Using an FWD to Determine the Structural Layer Coefficients for Flexible Pavement Materials
Construction and Performance of Ultra-Thin Bonded HMA Wearing Course
Effects of Sample Preconditioning on Asphalt Pavement Analyzer (APA) Wet Rut Depths
Insitu Measurement and Empirical Modeling of Base Infiltration in Highway Pavement Systems
Advanced Characterization of Crumb Rubber Modified Asphalts Using Protocols Developed for Complex Binders
An Examination of Operator Variability for Selected Methods for Measuring Bulk Specific Gravity of Hot-Mix Asphalt Concrete
Effect of Flat and Elongated Coarse Aggregate on Field Compaction of Hot Mix Asphalt
Effect of Using Silicone Rubber Molds on the Low-Temperature Binder Grading Parameters: BBR S(60) and m-Value
Improvement in the Determination of Failure Stress of Asphalt Binder and Test Repeatability through Sample Preparation in Direct Tension Testing
Techniques for Determining Errors in Asphalt Binders Rheological Data
A Method to Construct Thermal Stress Relief Joints in Asphalt Pavement
A Quantitative Evaluation of Stripping Potential in Hot Mix Asphalt Using Ultrasonic Energy for Moisture Accelerated Conditioning
Assessing the Economic Benefits from the Implementation of New Pavement Construction Methods
Estimation of Rutting Models by Combining Experimental Data From Different Sources
Fatigue and Permanent Deformation Models for Polymer-Modified Asphalt Mixtures
Flexible Pavement Design in Michigan: Transition from Empirical toMechanistic Methods
Long-Term Field Performance of Crack-and-Seat Rehabilitation Strategy
Propagation Mechanisms For Surface-Initiated Longitudinal Wheel Path Cracks
QuantitativeAnalysis of 3-D Images of Asphalt Concrete
Application of LTPP Seasonal Monitoring Data to Evaluate Volumetric Moisture Predictions from the Integrated Climatic Model
Data Collection and Management of The Instrumented Smart Road Flexible Pavement Sections
Low-Temperature Binder Specification Development: Thermal Stress Restrained Specimen Testing of Asphalt Binders and Mixtures
Measurement and Evaluation of Pavement Marking Retroreflectivity: South Carolina’s Experience
Modification of Binder with Acid Advantages and Disadvantages
Searching For Superior Performing Porous Asphalt Wearing Courses
Using Pavement Distress Data To Assess The Impact Of Construction On Pavement Performance

WashingtonState DOT Superpave Implementation

Paper 01-0149

Rita B. Leahy, PhD, PE

Fugro-BRE, Inc.

8613 Cross Creek Drive

Austin, TX78754

Phone (512) 977-1800

Fax (512) 973-9565

Email:

Robert N. Briggs

Materials Quality Systems Engineer

Washington State Department of Transportation

P.O. Box 47365

Olympia, WA98504-7365

Phone (360) 709-5411

Fax (360) 709-5588

ABSTRACT

Washington DOT (WSDOT) has aggressively investigated selected components and concepts of the SHRP/Superpave technology to include the following: Performance Grade (PG) binder usage and specification validation, gyratory mix design; the Superpave Shear Tester (SST); and field performance of Superpave mixes. The focus of this paper, however, is on field performance of Superpave mixes. Validation of the binder specification with respect to low temperature cracking was accomplished using binder and field performance data from 28 projects. The results were very encouraging: the original SHRP algorithm for binder selection correctly “predicted” field performance in 22 of 28 cases, whereas the LTPP algorithm SHRP algorithm for binder selection correctly “predicted” field performance in 26 of 28 cases. Since 1993, WSDOT has placed 44 projects that include some component of the Superpave technology. For 17 of these projects parallel Hveem and Superpave mix designs were conducted. In 13 of the 17 cases, the Superpave design asphalt content was equal to or greater than the Hveem design asphalt content, although the difference was usually no more than 0.2 percent. A conventional Hveem mix design was conducted for 18 of the original 44 projects placed using a PG binder (Hveem-PG). The remaining 26 projects were truly Superpave, i.e., the materials selection and mix design were established in accordance with the Asphalt Institute’s SP-2, Superpave Level 1 Mix Design. According to WSDOT practice the following numerical indices trigger maintenance: Pavement Structural Condition (PSC) =50, rutting =13 mm, or International Roughness Index (IRI) =500 cm/km. Although relatively “young,” all 44 projects are performing quite well. The average values of rutting, PSC and IRI (4, 91 and 121, respectively) are all well below the “trigger” values. With respect to rutting and PSC, the performance of Hveem-PG and Superpave projects is virtually identical. However, the ride quality of the Superpave projects is a bit rougher than that the Hveem-PG binder projects: IRI of 134 for the former and 103 for the latter. The higher values of IRI measured on the Superpave projects may be the result of the typically coarser aggregate gradation or differences in construction techniques.

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Mechanistic Analysis of Asphalt Pavements Using Superpave Shear Tester and Hamburg Wheel-Tracking Device

Paper No. 01-0138

Jian-Neng Wang*, Ph.D., Assistant Professor

Department of Civil Engineering

Ching-Yun Institute of Technology

2F, 68, LN 422, SEC 2, Chung-Shan E RD

Chungli 320, Taiwan

Tel: (886-3) 456-8088

Fax:(886-3) 466-4628

E-mail:

* Corresponding Author

Chien-Kuo Yang, Senior Engineer

Construction Management Department

Public Construction Commission

9F, 4, SEC 1, Chung-Hsiao W Rd

Taipei 100, Taiwan

Tel: (886-2) 361-8661

Fax: (886-2) 331-5808

E-mail:

Tsair-Yi Luo, Associate Engineer

Design Division

Taiwan Area National Expressway Engineering Bureau, 5F, 1, LN 1, Sec 3, Ho-Ping E Rd

Taipei 106, Taiwan

Tel: (886-2) 2701-8808

FAX: (886-2) 2701-8891

E-mail:

ABSTRACT

The study presents the comparative evaluation of permanent deformation and moisture damage of asphalt mixtures using the Superpave Shear Tester (SST) and the Hamburg Wheel-Tracking Device (HWTD). The damage analysis of simulated asphalt pavements is also included. The selected materials were a PG 64-22 asphalt binder and a sandstone aggregate with or without an anti -stripping additive. Repeated Shear test at Constant Height (RSCH) and the HWTD tests were performed for the evaluation of permanent deformation. The results showed the Superpave mixtures were less susceptible to permanent deformation than the Marshall mixture. It was found that the results of the HWTD tests performed at 40 o C were consistent with those of the RSCH tests. Two permanent deformation models were compared to relate plastic strain accumulation with the number of load repetitions. One selected for use in the SHRP A-005 contract is generally better than the other model. For moisture susceptibility evaluation of these mixtures, the results of the AASHTO T283 tests were consistent with those of the HWTD tests at 40 o C. The creep compliances calculated from the Frequency Sweep tests at Constant Height (FSCH) were applied to the KENLAYER program for pavement damage analysis. Based on the data and analyses in this study, the simulated asphalt pavements are considered more of a material and mix design problem rather than a structural problem. The use of creep compliances of the above mixtures could not successfully predict the pavement performance in comparison with results of the RSCH and HWTD tests.

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Impact of Gradation Relative to the Superpave Restricted Zone on HMA Performance

TRB Paper Number: 01-0141

Adam J. Hand 1

Quality Systems Engineer, Granite Construction Incorporated, 1900 Glendale Avenue, Sparks,

NV 89431, Office: (775) 352-1953, Fax: (775) 355-3431, email:

Amy L. Epps 2

Assistant Professor, TexasA&MUniversity, 503F CE/TTI Building, College Station, TX

77843-3136, Office: (979) 862-1750, FAX (979) 845-0278, email:

ABSTRACT

Significant controversy has revolved around the Superpave gradation specifications, in particular the restricted zone, since the completion of the Strategic Highway Research Program (SHRP). The reason for this is simple, dense-graded mixtures which encroach on the restricted zone had historically provided good performance prior to SHRP. However, current Superpave guidelines recommend that gradations passing through the restricted zone not be used. The objective of this paper is to provide a synopsis of recent research related specifically to the impact of the Superpave restricted zone on performance of hot mix asphalt (HMA). The evolution and purpose of the Superpave restricted zone are presented along with findings of both recently completed and on-going research. Studies involving laboratory and full scale accelerated performance tests of mixtures with gradations plotting above (ARZ), through (TRZ) and below (BRZ) the restricted zone were considered. The research reviewed clearly suggests that good performance can be achieved with fine-graded (ARZ and TRZ) mixtures and that no relationship exists between the Superpave restricted zone and HMA rutting or fatigue performance. Based on this it is suggested that the restricted zone recommendation be eliminated from the Superpave volumetric mixture design specifications.

Key Words: Superpave, aggregate specifications, restricted zone, gradation, HMA performance

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Comparison of the Engineering Characteristics of Asphalt Mixes To Field Data and Pavement Performance

Jonathan E. Crince

Staff Engineer

NTH Consultants, Ltd.

Gilbert Y. Baladi, Ph.D., P.E, Professor (corresponding author) and

Karim Chatti, Ph.D., Assistant Professor

MichiganStateUniversity

Dept. of Civil and Environmental Engineering

3546 EngineeringBuilding

East Lansing, MI48824

Phone#: (517)-355-5147

Fax#: (517)-432-1827

ABSTRACT

Over the past few decades, State Highway Agencies have continually modified their specifications regarding bituminous mixtures and/or have established new asphalt mixes such as Superpave. The engineering properties of the modified and/or new Superpave mixes have impacted the durability and performance of the pavement structures and they are needed as inputs to the pavement structural design procedure. Based on this need, the Pavement Research Center of Excellence (PRCE) at Michigan State University (MSU) undertook a research project to develop, implement and verify test procedures to characterize the engineering properties of Superpave and other conventional mixes. The two-year project, which was sponsored by the Michigan Department of Transportation (MDOT), consisted of field and laboratory studies. The laboratory investigation program was undertaken to characterize the physical and the engineering properties of various asphalt mixes. The field program included coring and nondestructive deflection testing (NDT) using a Falling Weight Deflectometer (FWD). This paper summarizes the laboratory and field test procedures and presents a comparison between the field and the laboratory test results. It is shown that: „ The laboratory test procedures can be used to characterize the engineering properties of the asphalt mixes. „ The laboratory test results correspond well to the backcalculated modulus values. „ The laboratory classification of the fatigue and rut potentials of the asphalt mixes corresponds to the observed field-performance. „ All laboratory and field results indicate that most superpave mixes have higher resilient modulus values and lower fatigue and rut potentials than other asphalt mixes.

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Effect of Superpave Gyratory Compactor Type on Compacted Hot Mix Asphalt (HMA) Density

M. Shane Buchanan

NationalCenter for Asphalt Technology

277 Technology Parkway

Auburn, AL36830

Phone: 334-844-6334

FAX:334-844-6248

e-mail:

E. Ray Brown

NationalCenter for Asphalt Technology

277 Technology Parkway

Auburn, AL36830

Phone: 334-844-6228

FAX:334-844-6248

e-mail:

ABSTRACT

The Superior Performing Asphalt Pavements (Superpave) gyratory compactor was developed as a tool in the Superpave mix design system to better simulate the field compaction of hot mix asphalt (HMA) mixes. All Superpave gyratory compactors are designed to meet the specification criteria found in AASHTO TP4. At the present time, AASHTO TP4 does not contain a precision statement. Furthermore, many agencies have reported differences in the bulk specific gravity of compacted samples from different Superpave gyratory compactors, which have been properly calibrated. Data is presented and analyzed from three gyratory compactor proficiency sample testing programs, from field project Superpave gyratory compaction comparisons, and from mix design and quality control/assurance results from a state DOT. The data was then analyzed to determine the statistical (precision) and potential project implications which result from the observed differences. The results indicate that the precision of the Superpave gyratory compactor is better than the mechanical Marshall hammer. However, there were significant differences between the bulk specific gravity of mixes compacted in different gyratory compactors. These differences could potentially lead to discrepancies during the mix design/verification and quality control/assurance testing of a given mix.

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Gradation Effects on HMA Performance

Adam J. Hand 1, James L. Stiady 2, Thomas D. White 3, A. Samy Noureldin 4 andKhaled Galal5

1 Quality Systems Engineer, Granite Construction Incorporated, 1900 Glendale Avenue

Sparks,NV89431, Office: (775) 358-8792, Fax: (775) 355-3431, email:

2 Staff Engineer, Kleinfelder, 5015 Shoreham Place, San Diego, CA92122,

Office: (858) 320-2000, Fax: (858) 320-2001, email:

3 Professor and Head, Mississippi State University, Mississippi State, MS

(662) 325-7185, Fax(662) 325-7189, email:

4 Pavement Research Engineer, Indiana DOT, Research Division, 1205 Montgomery Street,

WestLafayette, Indiana47906 Office: (765) 463-1521, Fax: (765) 497-1665, email:

5 Material Research and Accelerated Pavement Testing Engineer, Indiana DOT,ResearchDivision,

1205 Montgomery Street, West Lafayette, Indiana47906

Office: (765) 463-1521, Fax: (765) 497-1665, email:

ABSTRACT

The effect of gradation on hot mix asphalt (HMA) performance has long been acontentious issue. One objective of National Pooled Fund Study No. 176 was to evaluate the impact of gradation on the rutting performance of HMA mixture. To this end twenty-one Superpave mixtures were designed employing a range of materials, aggregate nominal maximum aggregate sizes, and gradations typical of those used throughout the United States. A suite of tests that included both laboratory and prototype scale loading were then used to evaluate the permanent deformation characteristics of the mixtures. Analysis of the data revealed that adequate performance could be obtained with mixture gradations plotting above (ARZ), through (TRZ), and below (BRZ) the restricted zone. Laboratory tests suggested that ARZ and/or TRZ gradations might provide better deformation resistance than BRZ gradations. However, prototype scale accelerated pavement testing did not show any clear trends in performance relative to gradation alone with respect to the restricted zone. This means that the restricted zone alone is not adequate to characterize gradation to ensure acceptable rutting performance and should therefore be omitted from Superpave specifications.

Key Words: rutting performance, aggregate, gradation, restricted zone, Superpave

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Effect of Aggregate Gradation on Permanent Deformation of Superpave HMA

Paper No. 01-2786

ARIF CHOWDHURY (Corresponding Author)

Engineering Research Associate, Texas Transportation Institute, 508H CE/TTI Building, Texas A&M University, College Station, Texas 77843-3135, Tel: 979-458-3350, Fax: 979-845-0278, Email:

JOSE D. C. GRAU

Ministry of Transportation, Spain, Email:

JOE W. BUTTON

Senior Research Engineer, Texas Transportation Institute, 508D CE/TTI Building, TexasA&MUniversity,

College Station, Texas77843-3135, Tel: 979-845-9965, Fax: 979-845-0278, Email:

DALLAS N. LITTLE

Senior Research Fellow, Texas Transportation Institute, 601 CE/TTI Building, TexasA&MUniversity,

College Station, Texas77843-3135, Tel: 979-845-9963, Fax: 979-845-0278, Email:

ABSTRACT

The restricted zone in aggregate gradation curve is one of the most controversial components of the Superpave mix design process. The restricted zone was adopted in order to reduce premature rutting in hot mix asphalt (HMA) pavements. The validity of the restricted zone requirement has been questioned by both the owner agencies and the paving and aggregate industries. The purpose of this paper is to examine the effect of the restricted zone on pavement rutting. Four different types of aggregate were studied: crushed granite, crushed limestone, partially crushed river gravel, and mixture of partially crushed river gravel as coarse aggregate with natural sand as fines. For each aggregate, HMA mixtures were designed using three different gradations: above the restricted zone, through the restricted zone, and below the restricted zone. Mixtures were tested using Superpave Shear Tester (SST). Four different tests were performed: simple shear at constant height, frequency sweep at constant height, repeated shear at constant stress ratio, and repeated shear at constant height. All twelve mixtures were also tested with Asphalt Pavement Analyzer (APA) to evaluate the rutting potential of those mixtures. From the analysis of the test results of SST and APA, we conclude that there is no relationship between restricted zone and permanent deformation. Further, these gradings passing below the restricted zone most often exhibited the greatest permanent deformation. Hardly ever did a gradation through the restricted zone yield the highest permanent deformation.