October 2010 – Vol. 4, No. 4 Partnering for Roadway Innovation

TERRA E-News is a quarterly electronic newsletter of the Transportation Engineering and Road Research Alliance. TERRA E-News brings you the latest research on pavement, materials, and related transportation engineering challenges, including issues related to cold climates.

MEMBER NEWS

Member Profile: Minnesota Local Road Research Board (LRRB)

The Minnesota Local Road Research Board (LRRB) has been a TERRA member since the alliance's formation in 2004. TERRA membership appealed to the LRRB because it offered a network of resources and information that is beneficial to county and city transportation officials, the population the LRRB was created to serve.

Established by the Minnesota Legislature in 1959 to support research on problems specific to local government road systems, the LRRB strives to share the latest transportation research applications with Minnesota's local road officials. LRRB membership includes county and city engineers, officials from the Minnesota Department of Transportation (Mn/DOT), and a representative from the University of Minnesota's Center for Transportation Studies. Its annual budget has grown from approximately $86,000 in 1960 to the current budget of about $2.2 million.

The LRRB has sponsored more than 200 research projects on a variety of topics in the last 15 years. Currently funded projects focus on improving the design, construction, maintenance and operations, or environmental compatibility of Minnesota's local roads.

Shoreview public works director Mark Maloney, chair of the TERRA Research and Implementation Committee, and Olmstead County highway engineer Michael Sheehan, chair of the TERRA Member and Partner Engagement Committee, represent the LRRB on the TERRA board.

TERRA offered the LRRB a "great avenue" to become involved in data and research exchange beyond Minnesota, Sheehan said. Through TERRA, state and local organizations can reduce redundancies in research and work together on mutually beneficial projects.

"Just because you cross the state line doesn't mean pavements and bridges are different," Sheehan noted. "Many times state and local units do a lot of the same research, and if we can pool our funds together and get additional information, it is better for all of us."

One such research partnership cited by Sheehan occurred when the Iowa Department of Transportation and county engineers researched the impact of heavy loads on county roads. Through the TERRA partnership and the use of the MnROAD facility, researchers collected data on damage done to roadways and bridges by vehicles carrying large amounts of agricultural or livestock-related weight, a topic applicable to many rural areas.

Looking forward, Sheehan also sees citizen demand for long-term pavement fixes as a growing issue. "People want pavements repaired or constructed properly without having to come back and do preservation work that impacts traffic," he said. "Through an organization such as TERRA, we can get the information we need to help make these things happen."

PROJECTS AND INITIATIVES

TERRA Innovation Series: Paving the way to a sustainable future

Sustainability in transportation was the focus of the fourth TERRA Innovation Series event held August 20 in Madison, Wisconsin. Participants learned about evolving strategies to reuse and recycle materials as part of asphalt and concrete road projects, such as recovering asphalt from recycled shingles and using fly ash to stabilize bases. These approaches can provide environmental benefits as well as cost-savings.

The TERRA Innovation Series consists of various events in TERRA-member states focusing on transportation engineering and road research. This year's offering, hosted by TERRA in cooperation with the Wisconsin Department of Transportation (WisDOT), a TERRA member, was held in conjunction with the 2010 Mid-Continent Transportation Research Forum.

TERRA co-chair André Clover, administrative engineer of best practices and legislative initiatives with the Michigan Department of Transportation (MDOT), and Rory Rhinesmith, division operations director with WisDOT, welcomed attendees.

WisDOT materials lab supervisor Tom Brokaw explained how recycled asphalt shingles (RAS) are an increasingly common component of hot-mix asphalt (HMA). In January 2009, WisDOT revised its standard specifications to allow use of RAS in asphalt pavements—specifications that are now being touted nationally.

"We worked closely with our public and private partners, including the state Department of Natural Resources, to develop a comprehensive set of specs that don't conflict with other existing regulations," Brokaw said. WisDOT specifications for contractors are permissive—not mandatory—and allow about 5 percent of HMA mix (by weight) to consist of postconsumer shingles. Brokaw said contractors are finding that use of RAS as part of the asphalt mix offers environmental and economic advantages as well as enhanced pavement performance.

A typical shingle is about 25 percent asphalt; when reheated, the asphalt can replace virgin material. The aggregate component of shingles enhances stability and surface friction, while fiberglass or cellulose fibers add strength to the overall mix. Using RAS as part of the asphalt pavement "recipe" helps address another problem:  a growing number of landfills refuse to accept postconsumer shingles. Workshop participants toured the Payne and Dolan HMA facility north of Madison where shingles are processed through shredders and magnets to ensure consistency and to remove nails.

WisDOT and its contractor partners are also paving the way when it comes to the reuse of concrete in highway construction. WisDOT quality assurance supervisor James Parry said virtually all concrete pavement can be recycled, either as shoulder material or as fill on grading projects, with the majority reused as base course beneath new pavement.

"Like asphalt, WisDOT specifications regarding recycling of concrete are voluntary, yet most contractors find the reuse option makes economic sense as a way to avoid disposal fees and costs associated with obtaining virgin materials," Parry said.

Wisconsin began recycling concrete as far back as 1983, but a more recent development is the increased use of fly ash (a byproduct of coal-fired power plants) to help replace the cement or "binder" ingredient in concrete. WisDOT specifications now allow fly ash to replace up to 30 percent of the cement component of concrete. The addition of fly ash helps hold down overall costs, results in a net decrease of greenhouse gases, enhances concrete's long-term strength, and helps minimize the damaging effects of water and salt.

Shingles, crushed concrete, and fly ash aren't the only things finding their way into Wisconsin roadways. WisDOT specifications allow pulverized toilets and glass, foundry and steel mill slag, along with bottom ash (another by-product of coal-fired power plants) to be used as base course underneath pavements. "Basically, we're using everything but the kitchen sink," Brokaw said. "Our goal is to be as sustainable and environmentally responsible as possible without compromising performance or safety."

Related resources:

• TERRA Innovation Series: Sustainability in Transportation
• 2010 Mid-Continent Transportation Research Forum
• Contact Tom Brokaw, Materials Lab Supervisor, WisDOT
• Contact James Parry, Quality Assurance Supervisor, WisDOT

MnROAD open house features SHRP 2 composite pavements

TERRA and the Minnesota Department of Transportation (Mn/DOT) hosted an open house August 23 at MnROAD to share research findings and provide a behind-the-scenes look at the live transportation laboratory along Interstate 94 near Albertville, Minnesota. The event was similar to the MnROAD open house held in 2008.

Bernie Arseneau, Mn/DOT director of policy, safety, and strategic initiatives, welcomed attendees on behalf of department commissioner Tom Sorel. MnROAD operations engineer Tim Clyne moderated the daylong event.

During his introduction, Clyne cited several MnROAD accomplishments, including an estimate that the facility saves the state about $33 million annually through implementation of a variety of research findings.

Clyne also discussed the implications of research findings to date. For example, he noted that the climate in Minnesota has proven to be a significant factor in pavement failures. In addition, some of the original cells were built thicker than necessary, based on the results seen from the first phase. "The designs that we had early on are too conservative," he added. "We can probably ease up a little bit without going too far the other way and causing a lot of distress. The recent test cells have been constructed thinner, generating earlier results."

An afternoon session at the open house focused on lessons learned from the SHRP 2 (Strategic Highway Research Program) composite pavement project, which consists of an asphalt surface over a new concrete pavement and "wet-on-wet" two-layer concrete paving. Field experiments at MnROAD are at the core of the four-year, $4 million SHRP 2 project, which is led by James Bryant, a Transportation Research Board senior program officer for renewal, one of four focus areas of SHRP 2, expressed enthusiasm about the project and the project team during brief opening remarks. Shreenath Rao, research engineer with ARA, gave an overview of the composite pavement project.

University of Minnesota civil engineering researcher Derek Tompkins, speaking on behalf of civil engineering associate professor Lev Khazanovich, talked about evaluating the instrumentation, material properties, and performance of the test sections. Mike Darter, principal engineer with ARA and principal investigator for the project, discussed the expected performance of the MnROAD composite pavement sections. "We don't think MnROAD will be out repairing these anytime soon," Darter said.

Next, Mn/DOT research engineer Mark Watson, manager of the SHRP 2 project at MnROAD, presented details about the design and construction of the project, which included WSB & Associates, Inc. for construction administration and C.S. McCrossan, Inc., as construction contractor. Among several highlights from the project, Watson noted that the diamond grind of one composite concrete pavement section with an exposed aggregate surface (cell 71) produced the quietest road surface in the country, with a tire-pavement noise recorded at 96.8 decibels.

Tony Johnson and Mike Nelles, both with the paving division of McCrossan, presented a case study of U.S. Highway 14 near Waseca, Minnesota, comparing the costs of composite paving with conventional paving. They explained that using recycled aggregate in the lower layer of composite pavement could be a viable and competitive alternative to conventional paving if Class A aggregates aren't readily available, if recycled concrete aggregate could be produced on or near the site for about half the cost of Class A, and if the construction team is capable of producing and paving at an equal rate to conventional paving. "If you can use recycled material," Nelles said, "it makes this a more attractive option."

Related resources:

• 2010 MnROAD Open House presentations
• SHRP 2 composite pavements research under way at MnROAD
  (TERRA E-News, July 2010)
• 2008 MnROAD Open House summary and presentations
• MnROAD website

VIDEO SPOTLIGHT: MnROAD

Visiting European transportation research groups seek opportunities for collaboration

TERRA was featured during a daylong visit to the University of Minnesota campus September 22 by members of FEHRL and ECTRI on a scanning tour of U.S. transportation research facilities.

FEHRL, the Forum of European National Highway Research Laboratories, provides a coordinated structure for the interests of more than 30 national research and technical centers from Europe, together with associated institutes from around the world. ECTRI, the European Conference of Transport Research Institutes, is an international nonprofit organization whose members are 27 major transport research institutes or universities from 20 European countries. Together, they account for more than 3,800 European scientific and research staff in the field of transport.

In addition to a series of laboratory tours, University faculty and several staff from the Minnesota Department of Transportation (Mn/DOT) discussed pavement research facilities and partnerships. Julie Skallman, Mn/DOT state aid engineer and TERRA board member, described the TERRA alliance; Maureen Jensen, Mn/DOT road research manager, reviewed the Mn/DOT-Sweden partnership; Tim Clyne, MnROAD operations engineer, provided an overview of the MnROAD test facility; and civil engineering associate professor Lev Khazanovich gave highlights of the University's pavement lab. Center for Transportation Studies director Laurie McGinnis, also a TERRA board member, guided the tour group around the University.

Minnesota was selected for a site visit because of its research facilities and its experience with international cooperation, according to Steve Phillips, FEHRL secretary-general. The aim of the scan was twofold: to identify what's missing in existing U.S. and European research facilities to meet current and emerging needs, and to recommend opportunities to use existing facilities and collaborate to develop new ones. The FEHRL-ECTRI tour included members from France, Great Britain, Spain, Germany, Hungary, Poland, South Africa, and Sweden.

For a number of years, Mn/DOT has taken part in international exchange agreements with various European countries, particularly the Nordic nations. On September 23, a similar tour was given to representatives from the Swedish Transport Administration. On August 26, a delegation from Russian transportation organizations visited campus for an information exchange and tours focusing on safety innovations. Skallman also accompanied that tour.

Related resources:

• Forum of European National Highway Research Laboratories
• European Conference of Transport Research Institutes

ANNOUNCEMENTS

TERRA Pavement Conference scheduled for Feb. 10, 2011

The TERRA Pavement Conference is scheduled for February 10, 2011, at the University of Minnesota Continuing Education and Conference Center in St. Paul, Minnesota. This one-day conference provides practical information to practitioners and others interested in pavement design, construction, rehabilitation, and maintenance. The emphasis of the conference is new materials and methods that can assist decision makers in providing the most cost-effective strategies for building, repairing, and maintaining pavement infrastructure.

The conference is intended for researchers, city engineers, county engineers, public works officials, maintenance superintendents, design engineers, consulting engineers, and others interested in pavement issues. The conference agenda and registration information will be posted in December.

For more information about the 2011 TERRA Pavement Conference, contact the College of Continuing Education, cceconf2@umn.edu, 612-624-4754, or visit the event Web page. To view information from previous conferences, visit the TERRA events page.

Upper Midwest Transportation Materials Summit, Nov. 3-4, 2010

The Michigan Department of Transportation, Michigan Technological University, and the Michigan Tech Transportation Institute—all TERRA members—are partnering to hold the Upper Midwest Transportation Materials Summit on November 3 and 4, 2010, in Houghton, Michigan. For more information, download the event brochure (1.8 MB PDF). To register, contact the Center for Technology and Training at Michigan Technological University, 906-487-2102. Advanced registration is required. Deadline: November 1, 2010.

Green streets and highways conference, Nov. 14-17

The American Society of Civil Engineers and the Transportation & Development Institute have scheduled the 2010 Green Streets & Highways Conference on November 14-17, 2010, in Denver. This conference is being held to address the rapidly growing interest and activity in sustainable transportation. In addition to opening and closing plenaries, the conference offers seven sets of concurrent technical sessions.

MAPA aphalt events planned

The Minnesota Asphalt Pavement Association calendar includes three upcoming events:

• MAAPT 57th Annual Asphalt Conference, December 8, 2010
  Northland Inn in Brooklyn Park, Minnesota
  Info: info@mn-aapt.org
• NAPA 56th Annual Meeting, February 6-9, 2011
  Waldorf Astoria & the Hilton at Bonnet Creek, Orlando, Florida
  Info: www.hotmix.org
• AAPT 86th Annual Meeting, March 27-30, 2011
  Marriott Waterside, Tampa, Florida
  Info: aaptinfo@gmail.com

ATSSA annual convention and traffic expo, Feb. 13-17, 2011

The American Traffic Safety Services Association (ATSSA) 41st Annual Convention and Traffic Expo is scheduled for February 13-17, 2011, at the Phoenix Convention Center in Phoenix, Arizona. The 2010 convention included roundtable sessions designed to facilitate a peer-to-peer exchange, workshops delivered by industry experts, and nearly 100 hours of training and certification programs.

CPAM annual concrete paving workshop, Mar. 10-11, 2011

The annual Concrete Paving Association of Minnesota (CPAM) Concrete Paving Workshop is scheduled for March 10-11, 2011, at the DECC in Duluth, Minnesota.

NRMCA seeks abstracts for concrete sustainability conference, Aug. 9-11, 2011

The National Ready Mixed Concrete Association is seeking abstracts for the 2011 International Concrete Sustainability Conference scheduled for August 9-11, in Cambridge (Boston), Massachusetts, at the Hyatt Regency Cambridge and the Massachusetts Institute of Technology Campus. The sixth annual conference will provide learning and networking opportunities on the latest advances, technical knowledge, continuing research, tools, and solutions for sustainable concrete manufacturing and construction. The conference is being held in conjunction with the MIT Concrete Sustainability Hub 2011 Industry Day scheduled for August 11, 2011. The deadline for abstract submissions is January 31, 2011.