A recent Equipment World’s Better Roads Online News Article discussed life-cycle analysis (LCA) emerging as a leading method of determining the environmental impact at both a macro and micro level in transportation projects in context of sustainability. The concrete pavement industry in particular is pushing for the increased use of this approach.
LCAs, broadly used in Europe and are included in “green” construction regulations in some countries, look at factors from the material being used, including aggregate, to the end of a pavement’s useful life. Everything in the process is considered—purchasing raw materials, material processing, manufacturing, construction, and the use of a pavement.
The Life Cycle Analysis 2017 Symposium at the University of Illinois at Urbana-Champaign focused on LCA for pavements, with the primary objective of reviewing industry use of the plans, pulling together a consensus of use, and determining ways to implement LCAs. “This was a great opportunity to see how pavement LCA is gaining wider acceptance,” said participant Eric Ferrebee, Technical Services Engineer-American Concrete Pavement Association (ACPA). “The symposium also provided a view of the practical, meaningful ways industry, the public sector and academia are working together to show the importance and value of LCA in highway, airport and roadway construction.”
Leif Wathne , Executive Vice President-ACPA and ISCP Director, also participated in a panel discussion. He stressed, “Meaningful advancement in sustainable practices and LCA will only be realized by fully marshaling and leveraging the expertise, know-how and innovative spirit of both paving industries, primarily through competition.”
According to the Federal Highway Administration’s (FHWA’s) Pavement Life Cycle Assessment Framework (July 2017) (click image to the right to download PDF), the most common uses of LCAs for pavements in North America include:
• Selecting a material or pavement structural design
• Evaluating the impacts of potential changes in a policy or specification
• Developing LCA tools for screening, detailed LCA for scoping, or project design
• Evaluating scenarios for network-level decisions and strategies for preservation, maintenance, and rehabilitation
• Developing material environment product declarations for pavement applications
Quantifying sustainability FHWA says LCA is one of four primary methods of measuring aspects of sustainability in order to set guidelines or benchmarks by which progress can be determined:
- LCA: Performance assessment—how a pavement performs compared to its “intended” purpose in relation to current standard practices. Looks at materials used or method of construction and how they compare to other methods considered standard with respect to longevity of a pavement’s service life.
- Life-cycle cost analysis (LCCA): Looks at the costs of a project to determine the economic impact of sustainable practices. The FHWA prefers LCCAs be used as a tool to support project decisions, and it recommends its RealCost program in processing LCCA data.
- Sustainability rating systems: List construction practices or features of a project that affect sustainability, and that measure the impact of these factors. The Pavement Life Cycle Assessment Framework sates, “In its simplest form, a rating system may count the implementation of every best practice equally (e.g., all worth one point), in which case the rating system amounts to a tally of the number of best practices used. In more complex forms, rating systems weight best practices (usually in relation to their impact on a selected definition of sustainability or a selected set of priorities), which can assist in choosing the most impactful best practices to use given a limited scope or budget. Many national and international pavement sustainability rating systems are currently available (e.g., INVEST, Greenroads, and Envision).”
- Materials and sustainability: Longevity is a sure test of a sustainable pavement, and this measure is driven by the materials used, both recycled and new. According to the National Concrete Pavement Technology Center (CP Tech Center), roughly 140 million tons of concrete is recycled each year in the United States, where more than 150,000 miles of highway are paved with concrete.
Historical concrete pavements
It’s hard to argue the longevity of concrete, as we marvel at the Roman structures scattered across Europe that have withstood millennia. And while we don’t have such a lengthy historical perspective in the United States, there are a number of concrete pavements that have withstood decades of use and abuse. For the ISCP article “Rock Solid History of Concrete—How Limestone, Rocks, and Volcanic Ash Built the Modern World”, please go to: https://www.concretepavements.org/2017/10/18/rock-solid-history-of-concrete-how-limestone-rocks-and-volcanic-ash-built-the-modern-world/.
The ACPA is creating a storehouse of old concrete pavements, with their first step being the creation of the Historic Concrete Pavement Explorer website last year. The map-based, mobile-friendly site provides details on these pavements, with potential for photo galleries, technical details and historical context. Jerry Voigt, CEO and ACPA President said, “The website represents ACPA’s commitment to the Task Force on Preservation of Artifacts from Historical Concrete Pavements. The task force is working to document concrete pavements and collect photographs and other artifacts for concrete pavements that are 75 years or older and/or which represent ‘firsts’ and other significant milestones throughout history.”
The launch of the site corresponded with the 125th Anniversary of the country’s first concrete pavement, placed in 1891 in Bellefontaine, Ohio, by George Bartholomew and WTG Snyder. This pavement was considered an engineering marvel at the time. A section of the concrete was on display at the 1893 Chicago World’s Fair and won first place for Engineering Technology Advancement in Paving Materials. For the ISCP article titled, “125th Anniversary Commemoration & Tour of First U.S. Concrete Street Held in Bellefontaine, Ohio (Audio & Video)”, please go to: https://www.concretepavements.org/2016/04/28/125th-anniversary-celebration-tour-of-first-u-s-concrete-street-held-in-bellefontaine-ohio-audio-video/.
The ACPA, the City of Bellefontaine, the Ohio Chapter of the ACPA, and the Task Force on Preservation of Artifacts from Historical Concrete Pavements held a celebration in July 2017 to commemorate an 11-foot replica of the original 7-foot-wide test strip of the 1891 pavement. “The test strip is part of a reconstruction project in downtown Bellefontaine, and it’s a big deal to our industry and to Bellefontaine,” said Bill Davenport, Vice President of Communications-ACPA. One of the project leaders, Shiraz Tayabji, Advanced Concrete Pavement Consultancy said, “The re-created test strip will provide service for another 100-plus years, linking the past, present and future of the concrete pavement industry.”
Davenport recently polled ACPA chapters, and through their submissions, the following list gives a snapshot of some of these long-lasting pavements:
1891 – Bellefontaine, Bellefontaine, Ohio:
For the PDF of the PROGRAM, click on image to the right; and for ISCP article titled, “Commemorative Program Now Available: 125th Anniversary Tour of the Oldest Concrete Street in America”, please go to: https://www.concretepavements.org/2016/05/03/commemorative-program-now-available-125th-anniversary-tour-of-the-oldest-concrete-street-in-america/.
1906 – Portland Street, Calumet, Michigan
1907 – Van Buren, Arkansas
1907-1909 – County road in Mahaska County, Iowa
1908 – Grand Forks, North Dakota
1909 – Cemetery Road, Eddyville, Iowa
1909 – 6th Street, Duluth, Minnesota
1910 – Multiple city streets, Grand Forks, North Dakota
1912 – Central Avenue, Urbana, Illinois
1913 – Dollarway Pavement, White Hall, Arkansas
1914 – Belknap Place, San Antonio, Texas
1914 – Third Street, Delevan, Illinois
1914 – River Road, Moscow, Iowa
1915 – “Original seedling mile,” Grand Island, Nebraska
1916 – Westminster Street, Salt Lake City, Utah
1916-1927 – Multiple city streets, Fort Collins, Colorado
1918 – County road in Woodbury County, Iowa
1919 – Sunset Highway, Spokane, Washington
Belknap Place in the Monte Vista Historic District of San Antonio, Texas was honored with ACPA’s 2016 Lifetime Pavement Recognition Award, commemorating it as the oldest concrete pavement in Texas. It was created using a process called “Granitoid”—a two-lift system that features coarse aggregate in the bottom lift and hard granite aggregate in the surface course. Cars, trucks and buses continue to travel across this pavement, and officials say there are few signs of faulting or deterioration. Belknap Place was the site for the 11th ICCP Conference “History of Cement in Texas Field Trip” this past August. From the 11th ICCP Program. To download the PDF of the 11th ICCP Program, please go to: https://www.concretepavements.org/11thConf/wp-content/uploads/2016/08/1_11thPROGAUG_TUESDAYAUG23_ONLINE.pdf
To read the entire Equipment World article titled “, please go to: https://www.equipmentworld.com/sustainability-measures-key-to-long-lasting-concrete-pavements/
Home Page Photo: Workers pour concrete on a roadway in Highlands Ranch,
Colorado, for one of the largest concrete pavement preservation projects.