Pavement Preservation

The Moving Ahead for Progress in the 21st Century Act (MAP-21) defines pavement preservation as programs and activities employing a network level, long-term strategy that enhances pavement performance by using an integrated, cost-effective set of practices that extend pavement life, improve safety, and meet road user expectations.

When the right treatment is applied to the right road at the right time, roads can be kept in good condition instead of performing costly rehabilitation and reconstruction alternatives later in the pavement’s life when the structure has deteriorated.

Pavement Preservation Group Study

The pavement preservation group study is quantifying the life-extending and condition-improving benefits of different pavement preservation treatments and treatment combinations on low-volume and high-volume roadways in both northern and southern climates. By determining the field performance of treatments applied at various stages of pavement life and decay, historically broad performance expectations for various preservation options will be discretely quantified to allow agencies to make objective decisions regarding treatment selection. A second focus of the study is to develop specifications and recommended guidelines for quality assurance testing and inspection of pavement preservation treatments.

Southern Test Locations

NCAT Test Track

Treatments in various sections of the Test Track

Lee County Road 159

Low-volume traffic test sections on Lee County Road 159

U.S. Route 280

High-volume traffic test sections on U.S. Route 280


The PG study began with NCAT’s fifth research cycle in 2012 and consisted of 23 pavement preservation treatments or treatment combinations applied to 100-foot long test sections located on Lee County Road 159, a low-volume, high truck traffic road in Auburn, Alabama. In addition, two sections with significantly different initial conditions were left as untreated control sections. At the time of treatment, the existing pavement was 14 years old, consisted of a 5.5-inch hot-mix asphalt layer, and varied from good to poor condition.

In 2014, pavement preservation treatments were applied to several Test Track sections at predetermined distress levels. Traffic and examination of these sections will continue throughout the 2018 research cycle.

For the 2015 research cycle, 34 pavement preservation treatments or treatment combinations were placed on a section of U.S. Route 280, expanding the research scope to include a higher volume roadway. These sections serve as a compliment to the existing sections on the Test Track and Lee County Road 159. Sections on U.S. 280 are 0.1 miles in length on the outside lane of the two-lane eastbound highway. Control sections with low and high levels of cracking, rutting, IRI and texture are also included. The existing pavement was nine years old at the time of treatment and had an average thickness of 9.9 inches.

In an effort to provide results that are practical and implementable in both northern and southern U.S. climates, many of the same preservation treatments installed in Alabama are being investigated in Minnesota. Open graded friction courses (OGFCs) are being tested at MnROAD, a pavement test track owned and operated by the Minnesota Department of Transportation. The northern pavement preservation experiment sections are located on U.S. Route 169, a high-volume road, and County State Aid Highway (CSAH) 8 in Mille Lacs County, a low-volume road. This study includes treatment selection, test site selection and layout, scheduling, construction, performance monitoring, and data activities to quantify the life-extending benefits of pavement preservation treatments using MnDOT materials and construction methods. Find out more about the NCAT/MnROAD partnership here.