Welcome from UW–Madison’s Andrew Hanz

Happy New Year! 2008 marked the 10th anniversary of the Wisconsin Highway Research Program. During those years, the four Technical Oversight Committees have collectively completed more than 60 projects. In the past six months, WHRP analyzed the outcomes of these research efforts to quantify how well WHRP research has been implemented into WisDOT practices.

In our analysis, we grouped the projects in four categories: implemented, not implementable, further WHRP-funded research in progress and projects pending action. Projects were considered implemented if they resulted in a tangible change in WisDOT guidance documents. Projects pending action were those whose conclusions required further TOC action or follow-up with WisDOT tech teams.

Results of the analysis are shown here. We concluded that WHRP research has indeed been successful in moving research into practice; however, there is still room for improvement: 67 percent of projects either need further action or additional research.

As a result of this analysis, the TOCs funded two projects for the fiscal year 2010 funding cycle based on recommendations from previous research with potential for implementation. WHRP will update the implementation figures annually to allow TOCs to continue to consider projects “pending action” when developing future research.

To ensure that future research provides usable results, WHRP is working with the TOCs to assess potential for implementation while formulating and prioritizing new research ideas. To support this effort, WHRP added a section to the Request for Proposals template that requires comments on intended outcomes and the specific WisDOT guidance documents that the research is intended to change.

WHRP will continue to work toward improving the rate of research implementation through these and other efforts. I would personally like to thank the TOC chairs and members for providing their input and assistance in this analysis and for integrating these new policies into their meetings.

Andrew Hanz, WHRP Program Manager
University of Wisconsin–Madison, Department of Civil & Environmental Engineering
ajhanz@wisc.edu
(608) 262-3835

10 Years of WHRP: A 10-to-1 Return on Research

WHRP gratefully acknowledges the contributions of its committee members, investigators and staff over the past decade as well as the support from WisDOT and the University of Wisconsin. WHRP’s research activities have helped address and solve critical highway needs in Wisconsin.

WHRP used this 10-year milestone to “mint” and distribute a special issue $10 bill, reminding stakeholders that every $1 invested in highway research yields a benefit of $10 or more.

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WHRP Focuses on MEPDG

AASHTO’s Mechanistic-Empirical Pavement Design Guide (MEPDG) represents a major step forward in pavement design. In Wisconsin, MEPDG methodology can be employed to analyze and validate pavement designs using local materials, conditions and design configurations. This is considered a new-generation design methodology when compared with WisDOT’s current procedures for designing rigid and flexible pavements, based on AASHTO design equations published in the 1972 empirical design manual.

WHRP has actively pursued MEPDG research for several years, funding more than a dozen research projects related to MEPDG issues and participating in two related Transportation Pooled Fund studies. A detailed review of these activities is available. MEPDG methodology still requires further research efforts before it can become the new effective design standard for Wisconsin. The TOCs have identified research needs in several key areas, including:

• Characterization of Materials. Values for material properties and mechanical performance; effects of recycled materials.

• Calibration and Validation. Local calibration; comparison of parallel design; field evaluation methods; performance data over time; as-built material properties.

At its recent meeting on January 23, the WHRP Steering Committee approved two MEPDG-related projects. The first, “HMA Fatigue and Low Temperature Properties to Support Mechanistic-Empirical Pavement Design Guide,” is an 18-month study funded at $70,000. Study objectives are to establish a range of tensile strength and creep compliance properties of representative Wisconsin HMA mixtures; recommend how to use these values in the MEPDG; and identify any needed changes to WisDOT low-temperature HMA specifications.

The Steering Committee also approved “Laboratory Study of Concrete Properties to Support Implementation of the New AASHTO Mechanistic-Empirical Pavement Design Guide,” a 27-month study funded at $180,000. This comprehensive effort involves testing a spectrum of Wisconsin aggregates against a cross section of representative cementitious materials on three tests of the fresh concrete mix and seven tests of the hardened concrete.

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Highlights from WHRP Steering Committee

The WHRP Steering Committee held its quarterly meeting January 23 in Madison. Daniel Yeh, WisDOT's new research administrator, chaired the meeting and introduced two other new members: Jeff Tormey of McClure Engineering who now represents the Association of Consulting Engineering Companies of Wisconsin, and Dwight McComb who returns to the Steering Committee as the FHWA representative of the Wisconsin Division.

The major item of business was approval of 15 TOC-proposed research activities for federal FY 2010, beginning October 1, 2009, for a total investment of approximately $840,000. Four of the projects are pooled fund studies and three are amendments to previous Wisconsin studies. The eight new Wisconsin projects are:

A key discussion topic at the meeting was the importance of collaborating on research projects with other states whenever possible. WisDOT is looking in particular at increased efforts to collaborate with Minnesota DOT as part of a larger partnership initiative by the governors of the two states.

No new projects in the area of data integration were funded this year. Changing information technology and data warehousing procedures within WisDOT, along with limited resources for undertaking large IT projects, have made it very challenging to move forward in this area. For this reason, Daniel Yeh convened the members of the Data Integration TOC and led a discussion about the feasibility of continuing these projects. The group reached consensus that two of the three existing data integration studies should be canceled. WHRP will continue to look for opportunities to increase data access for investigators.

The Steering Committee also reviewed and approved revised researcher selection procedures developed and piloted by the TOCs in late 2008. The new procedures, developed with significant input and guidance from Peg Lafky, emphasize objectivity and transparency in selection of investigators.

The committee reviewed a draft white paper titled “Opportunities for WHRP to Support WisDOT Efforts to Implement the MEPDG.” The paper outlined a number of research needs related to pavement design and geotechnical considerations such as aggregate sources and stabilization alternatives. WHRP hopes the paper will be used in the future to plan MEPDG-related research.

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Project status at a glance

As of December 31, 2008, there were 32 active WHRP projects. Four projects were completed during the last six months.

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Research in Focus

New Guidelines to Help Extend the Service Life of PCC Pavement Repairs
0092-07-03, Guidelines for Improving Full-Depth Repair of PCC Pavements in Wisconsin

After 20 to 25 years of service, the portland cement concrete used by Wisconsin in its highway construction projects typically deteriorates, leading to pavement cracking, joint spalling and other distresses. Once this damage occurs, the service lives of these PCC pavements are usually extended by one or two rehabilitation efforts before the pavements are entirely reconstructed.

Rehabilitation involves, among other activities, full-depth concrete repairs, a technique that restores the structural integrity and rideability of pavements by removing and replacing isolated areas of deteriorated concrete, particularly those near joints and cracks. But these rehabilitated areas themselves deteriorate in 12 to 15 years, after which a second rehabilitation is required.

To extend the service life of PCC pavement rehabilitations, Dr. Michael Darter has developed recommendations for improving the performance of full-depth repairs. The final WHRP report documents best design practices, materials selection, and construction and inspection methods to avoid the risk of early cracking and other distresses in rehabilitated pavements. The report also presents a consistent approach for identifying needed repairs as well as guidance for selecting the most cost-effective repair depending on the situation.

These recommendations were developed using information available from existing WisDOT guidelines and other relevant literature and research. They are intended to supplement but not replace current specifications for PCC pavement repair throughout the state.

For details, see the WHRP study’s project page or contact Jim Parry, chair of WHRP Rigid Pavements TOC, at (608) 246-7939.

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Porous pavements may enhance safety, but can they be used in winter environments?
0092-07-01, Investigation of the Use of Open Graded Friction Courses in Wisconsin

Open graded friction courses are increasingly being used by state DOTs throughout the United States. OGFCs are porous asphalt pavements that quickly drain water from road surfaces, reducing the frequency of wet-weather accidents caused by hydroplaning. OGFCs also improve tire traction and minimize tire spray and noise.

Despite their safety benefits, OGFCs have not historically been used in Wisconsin because of questions about their cost and performance in winter environments. To address these questions and the possibility of using OGFCs in the state, Dr. Richard Root has conducted a WHRP study that includes a literature review, survey of states and cost analysis.

The literature review and survey focused on determining whether OGFCs are successfully being used in locales that have similar climatic conditions to Wisconsin, especially states with freeze-thaw cycles. The cost analysis compared the cost of OGFCs to that of standard asphalts currently in use in Wisconsin.

An interim report, to be published in January 2009, shows that while OGFCs are beneficial in more moderate climates, their use is problematic in winter climates. OGFCs freeze more quickly than other pavements, and removing snow and ice from them is more difficult, requiring much heavier and more frequent applications of deicing salts.

The report recommends that Wisconsin, like other states with frigid winter climates, should not employ OGFCs until the technology is enhanced for viability in colder weather.

For details, see the WHRP study’s project page or contact Judie Ryan, member of the WHRP Flexible Pavements TOC, at (608) 246-5456.

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Regional and National Collaboration

2009 NCAUPG Conference Addresses Asphalt Issues

Stakeholders in the Wisconsin asphalt community benefit from their participation in the North Central Asphalt User/Producer Group, an organization of government and industry representatives from 12 states in the central and north central United States and two Canadian provinces. NCAUPG provides a forum for its members to address the many common concerns facing the asphalt industry in this region.

In early February, the annual NCAUPG technical conference convened in Madison. The two-day event covered a wide range of topics related to asphalt, including technical innovations, advances in recycling and sustainability, and market trends and issues. The conference included presenters from across the region and the United States, including FHWA, the National Asphalt Pavement Association, the North Central Superpave Center and the Asphalt Pavement Alliance. Wisconsin presenters included representatives from WisDOT, UW–Madison, the Wisconsin Asphalt Pavement Association and asphalt producer Payne & Dolan of Waukesha.

For more information about Wisconsin’s participation in NCAUPG or this conference, contact Hussain Bahia at UW–Madison.

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Modified Asphalt Research Center—MARC

Investigators at UW–Madison’s Modified Asphalt Research Center made significant progress over the last several months on research related to skid resistance, pavement friction and noise. Advances in this area will help make asphalt pavements safer and quieter, a shared concern of the WHRP Flex TOC.

• Texture Evaluation and Prediction. MARC researchers worked on laboratory procedures and prediction models for the evaluation of macro- and microtextures of asphalt pavements. Results will help form a mixture design methodology that will address not only pavement strength and durability but also traffic safety, motorist comfort and reduced pavement-tire noise.

• Measuring Sound Dissipation. The team at UW–Madison has been developing a sound absorption device to measure a pavement’s ability to dissipate sound energy, similar to other devices employed at the National Center for Asphalt Technology. Open graded friction courses and stone matrix asphalt have the ability to absorb the sound resulting from pavement-tire interaction, and MARC’s waveguide device will be an important tool in measuring the energy absorbed or reflected by these pavements.

• Field Testing Devices in the Lab. MARC researchers are evaluating the potential for field testing devices in obtaining information about the textural and frictional characteristics of mix designs before they reach the field. As part of an FHWA equipment loan program, UW–Madison is evaluating both a Circular Texture Meter and a Dynamic Friction Tester.
  

For more information about these or other MARC research projects, contact Hussain Bahia or Carl Johnson.

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WHRP at the TRB Annual Meeting

Wisconsin investigators shared the results of WHRP-sponsored activities at one of the largest stages for transportation research: the 88th annual TRB meeting. Held in January in Washington, D.C., the meeting included sessions featuring two WHRP investigations:

• Nicholas Hornyak of Collins Engineering (formerly of Marquette University) and James Crovetti of Marquette University coauthored research titled "Analysis of Load Pulse Durations for the Marquette Interchange Instrumentation Project." The presentation was part of a session addressing the modeling and analysis of pavement response and deformations.

• Craig Schuettpelz, Dante Fratta and Tuncer Edil of UW–Madison coauthored research titled “Evaluation of the Zone of Influence and Stiffness Improvement Due to Geogrid Reinforcement in Granular Materials.” This presentation was included in a session that addressed the establishment of material properties, standards and procedures to implement geosynthetics into mechanistic-empirical design procedures.

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New NCHRP Research Related to the Resilient Modulus Workshop

In October 2007, the North Central Asphalt Research Partnership pooled fund conducted a workshop on laboratory-resilient modulus test methods for subgrade materials. At that time, a highly anticipated NCHRP synthesis report on that topic was nearing completion.

NCHRP recently published its findings as Synthesis Report 382: “Estimating Stiffness of Subgrade and Unbound Materials for Pavement Design.” This report will be of interest to pavement researchers and highway practitioners alike. The report is available as a PDF on the workshop’s Web page.

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Outreach

Year-in-Review Webinar

WHRP is taking advantage of new technology transfer methods to communicate the program’s progress and accomplishments. In November 2008, WHRP used Web-based seminar (webinar) software to give a year-in-review presentation to an audience that spanned the state.

The webinar covered WHRP research, implementation, technology transfer and outreach activities as well as program updates for FY 2008 (October 1, 2007, to September 30, 2008). Participants from WisDOT’s Northeast and Southwest regions and from its Madison offices watched the presentation online while listening to the presenters in real time. All participants were able to freely exchange their ideas in the question-and-answer sessions.

The webinar proved to be a highly efficient and effective means of communication, allowing dialogue among attendees while minimizing travel time and costs. WHRP plans to make the year-in-review presentation an annual activity, and it will make even more use of webinars in the future.

For more information about the webinar, contact Andrew Hanz at UW–Madison or Peg Lafky at WisDOT.

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Contractor-Engineer Conference

In January, WisDOT and the Wisconsin Transportation Builders Association co-hosted the annual Contractor-Engineer Conference. During the conference, WisDOT Research & Communication Services Section Chief Daniel Yeh moderated a presentation about WHRP’s activities. Hussain Bahia and Andrew Hanz used this opportunity to outline key technical findings from WHRP research activities in its five technical areas. They also addressed and answered questions about WHRP’s support of WisDOT’s implementation of the MEPDG.

For more information about WHRP’s participation in this conference, contact Andrew Hanz.

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Implementation Report

Project disseminates techniques for rehabilitating corrosion in concrete bridges
0092-06-08, Implementation of Rehabilitation Techniques for Concrete Bridges

Concrete bridges in Wisconsin and other northern states are susceptible to corrosion caused by winter deicing salts, especially at the ends of girder beams.

A 2005 WHRP project (0092-01-06) showed that coating prestressed concrete beam ends with polymer resins is the most efficient and cost-effective way to prevent and repair this corrosion. Researchers also developed a database and expert system software to assist in the diagnosis of concrete bridge deterioration and development of maintenance and repair options.

Professor Al Ghorbanpoor and a research team at the UW–Milwaukee are conducting an implementation project to communicate the results of this study to WisDOT personnel and the concrete girder industry at large.

The team developed a set of PowerPoint presentations and handouts summarizing the results of the study, distributed these materials to WisDOT personnel and presented findings at the Paint and Coatings Expo held January 27–30, 2008, in Los Angeles.

The team also submitted generic specifications language to WisDOT based on a literature search identifying accepted national standards for the application of protective coatings to the ends of prestressed concrete bridge girders. In the next few months, these standards will be incorporated in the Wisconsin Bridge Manual and Standard Detail Drawings.

For details, see the WHRP implementation’s project page or contact Travis McDaniel, co-chair of WHRP Structures TOC, at (608) 266-5097.

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About WHRP
www.whrp.org

The Wisconsin Highway Research Program was established in 1998 by the Wisconsin Department of Transportation to conduct research on highway materials and construction methods. WHRP is administered by the UW-Madison Department of Civil and Environmental Engineering. A Steering Committee chaired by the WisDOT Research Administrator provides policy direction to the WHRP Technical Director, Program Manager and five Technical Oversight Committees chaired by WisDOT engineers. The TOCs focus their work on Flexible Pavements, Rigid Pavements, Geotechnics, Structures and Data Integration. The Steering Committee and TOCs are composed of representatives from WisDOT, FHWA, academia and industry.

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