If you are an ACPA member, please contact Eric Ferrebee for editing access to the content of this resource.
Concrete Pavement Thickness Design
Concrete pavement thickness design has evolved over the years since the first concrete pavement was built back in the 1890's. Most of the early pavement designs were largely empirical with designers relying on past observations from previous practices and early road tests such as the Bates Test Road. In the late 1950's the AASHO Road Test was performed. Over 350 concrete pavement sections were empirically designed and tested over a span of two years. At the time, it was thought that a minimum of 8 inches was required for a concrete pavement. At the end of the test only about 25 percent of the concrete sections were considered failed. The data taken from the AASHO road test was developed into the AASHO Interim Guide for the Design of Rigid and Flexible Pavements, which eventually evolved into the 1993 AASHTO Design Equation. This design method is featured in ACPA's WinPAS pavement thickness design software.
The AASHO road test applied a relatively limited amount of load repetitions (1.1 million over two years) to the tested sections. The observed response from the applied and environmental loadings became inadequate to design pavements for long life applications under heavy loading. For this reason, AASHTO later developed the Mechanistic-Empirical Pavement Design Guide (MEPDG) which would eventually evolve into DARWin-ME and later AASHTOWare Pavement ME. This tool is intended to evolve over time as data is continually gathered from long-term pavement performance (LTPP) sections.
There are a number of concrete pavement thickness design methods that have been developed over the years. The various design methods have since been developed into computer software. ACPA provides a number of pavement design software to help design new pavements and overlays for applications such as streets, roads, highways, airfields, and industrial facilities as well as special applications such as pervious concrete pavement.