Victor Lee Gallivan

Investigation of Properties of Plant-Produced Reclaimed Asphalt Pavement Mixtures

The influence of reclaimed asphalt pavement (RAP) content on the mixture and recovered binder properties of plant-produced hot-mix asphalt (HMA) was examined by studying the complex moduli of RAP mixtures and binders. RAP was added at 15%, 25%, and 40% levels to HMA with PG 64-22 and at 25% and 40% levels to HMA with PG 58-28 binder. In addition, control mixture samples with PG 64-22 and no RAP were also collected and tested for comparison. Compacted specimens were tested to determine the complex dynamic moduli (|E*|) at three temperatures. Complex shear moduli (|G*|) of the binders recovered from these HMA samples, RAP samples, and original binders were determined at the same test temperatures. Low-temperature creep compliance and indirect tensile strength of the mixtures were also determined, and these results were used to estimate the critical cracking temperature of the pavement. Statistical analysis indicated that there were no differences in mean strength and |E*| of the mixtures at the 15% and 25% RAP levels. Some differences between the control mixture and the 40% RAP mixtures were found only at the higher test temperatures.

Benefits of Warranties to Indiana

Several states have experimented with performance warranties on hotmix asphalt (HMA) pavements. Generally, the quality of warranted HMA is perceived to be better. Also, it is believed that HMA extends pavement life. Various methods can be used to define the benefits of warranties. Benefits have to be related to the performance life of the pavement and the cost. This study documents the effectiveness of the Indiana 5-year performance warranties and demonstrates that projected lifetimes of the warranted HMA pavements are being extended an additional 9 years in evaluations of international roughness index (IRI) and rutting criteria over the typical design life of the pavements. The cost-effectiveness of the warranted pavements, even though the initial costs are 5% to 10% higher, is significant when one considers the extended life of the warranted pavements. Overall cost to maintain the network Interstate smoothness at a constant 2002 value is

Improving Quality Control of Hot-Mix Asphalt Paving with Intelligent Compaction Technology

1.08 billion with warranties and

Intelligent Compaction for Improving Roadway Construction

1.47 billion for nonwarranty projects, or a savings for warranty projects of 27%. Warranty projects require fewer demands on budgets and provide for lower network IRI at the same effective age of the pavements. Indiana HMA warranties have accomplished the initial goals of both the Indiana Department of Transportation and the HMA industry by providing smoother and safer pavements with fewer defects over a longer period of time, which reduces delays and congestion. At the same time, the economic benefits of warranted pavements are significant.

A Sensing-Information-Statistics Integrated Model to Predict Asphalt Material Density With Intelligent Compaction System

This paper answers whether existing intelligent compaction (IC) technology can be used in a practical way to improve the quality control (QC) process for hot-mix asphalt (HMA) paving projects. Specifically, the paper investigates the use and the benefits of IC technology for tandem drum vibratory rollers used to construct HMA materials. There is a need to improve QC practices for most typical HMA paving operations. This paper identifies and discusses major shortcomings in conventional compaction equipment and current QC practices. The use of IC technology can address these shortcomings and provide innovative QC tools to contractors and agencies. The paper is based on the findings of the Intelligent Compaction Pooled Fund (ICPF) project that included 16 field demonstration projects in 12 participating states. The ICPF projects were actual highway construction projects in which various pavement materials were placed and compacted with both conventional compaction equipment and rollers that were equipped with IC technology from various suppliers. Eight of the projects included placement and compaction of HMA materials. On these projects, IC was used for only a portion of the project. A case study of the Wisconsin project illustrates the benefits that could have been obtained if IC technology and specifications had been used for the entire project from beginning to end.

Leveraging Intelligent Compaction and Thermal Profiling Technologies to Improve Asphalt Pavement Construction Quality: A Case Study

Quality control (QC) and quality assurance (QA) tests for compaction in construction projects are typically based on density measurements. The main issue regarding density-based QC/QA specifications is that they do not relate to mechanistic properties of materials and modulus that are critical to mechanistic-empirical types of pavement designs (MEPDG). Another concern is that the depth of influence of density measurement is restricted to 300 mm that is insufficient to detect deeper weak spots that are critical during subgrade or subbase compaction. In intelligent compaction (IC) technology the stiffness of the materials can now be identified to provide real-time opportunities to address the above issues and uniformity during compaction of the materials. Intelligent compaction rollers are equipped with roller-integrated measurement systems, global positioning system (GPS) and on-board displays that provide real time and 100%-coverage evaluation of the materials being compacted. Therefore, IC can bridge the gap between roadway design and roadway performance. Improved pavement engineering leads to the improvement of the design and construction of roadways and extends the life of pavements. This paper provides guidelines for future QC/QA specifications based on extensive IC field validations and knowledge gained from the US FHWA/Transportation Pooled Fund (TPF) IC study. The guidelines will cover all roadway materials from the ground up including subgrade, subbase (including granular and stabilized base), and hot mix asphalt materials. The aspects of the guidelines include: (1) qualifying IC equipment, (2) specifying GPS equipment and requirements, (3) validating IC systems and GPS operations onsite, (4) mapping existing support materials, (5) selecting in-situ tests for calibration, (6) specifying data collection procedures for IC and in-situ tests, and (7) analyzing data and producing reports. All the above come with real world experiences from more than a dozen full scale IC projects. By implementing the IC QC/QA guidelines proposed in this paper, the process of designing and constructing our roadways will lead to the improved performance of roadway systems.

Development of a Test Method to Measure the Quality of Milling Operations in Asphalt Pavements

Intelligent compaction (IC) is an innovative technology that has been used in road and earthwork construction. However, the current IC technology is unable to measure material density directly as the acceptance criteria by owner agencies. To tackle this issue, the authors have developed a sensing-information-statistics integrated model to predict asphalt material density for 100% coverage of construction area. Instrumented with the satellite navigation system, accelerometer, and infrared sensors, IC rollers measure mechanical responses of roller drums and material temperature in real time. With these measurements, panel data models-including both the multivariate linear and nonlinear models-were developed to predict asphalt material density. A reasoning model was proposed to estimate idiosyncratic errors due to uncertainty of measurements. An information management software was developed to analyze IC measurements with univariate statistics and geo-statistical models. Statistical models were implemented and validated with data collected from four paving projects in the US. Results indicate that the multivariate nonlinear panel data model can predict asphalt material density at the project level for 100% coverage of the construction zone within reasonable accuracy. Therefore, this model may serve as an enhanced quality control and acceptance tool for asphalt pavement construction to improve consistency and uniformity and long-term performances.

Development of a systematic method for intelligent compaction data analysis and management

Intelligent compaction (IC) is an emerging technology with rollers equipped with global navigation satellite system (GNSS), an accelerometer-based measurement system, and an onboard color-coded display for real-time monitoring and compaction control. Paver-mounted thermal profiling (PMTP) is used to monitor asphalt surface temperatures behind a paver with a thermal scanner, and to track paver speeds, stops, and stop durations. Leveraging both IC and PMTP technologies allows for paving and compaction controls in real time, and for executing appropriate adjustments as needed. A case study is used to demonstrate the advantage of using both IC and PMTP over conventional operations. Postconstruction asphalt coring and tests, as well as pavement profile surveys were conducted to provide asphalt density data and pavement smoothness acceptance data for comparison and correlation analysis with IC and PMTP data. The data from 2 days of operations, one without the Material Transfer Vehicle (MTV) and another with the MTV, were analyzed and compared to illustrate the benefits of using IC, PMTP, and MTV for producing quality pavement products. Durability and smoothness are two key construction qualities for agencies and users of hot mix asphalt (HMA) pavements. These two factors also affect the long-term structural and functional pavement performance.

Influences of intelligent compaction uniformity on pavement performances of hot mix asphalt

Cold milling operations have been used for more than two decades in Indiana, but little attention was given to the quality of the operations. Several alternatives for evaluating surface macrotexture were considered as a quality measure. ASTM E965-96 was selected as the best procedure on which to base evaluation of milled surfaces. The Indiana Department of Transportation developed Test Method ITM 812-03T to make the ASTM procedures workable for milled surfaces. The initial quality of hot-mix asphalt (HMA) construction directly affects the long-term performance and the service life of a transportation facility. It is directly dependent on the quality of the aggregates and binders and the production and laydown operations. Construction concerns include surface preparation, which is the removal of distressed materials to develop a stable working platform on which HMA materials can be placed. Indiana HMA contractors were experiencing numerous problems in meeting volumetric and density quality requirements on ...