VERIFICATION OF THE STRUCTURAL BENEFITS OF CONCRETE SHOULDERS BY FIELD MEASUREMENTS

Abstract

The justification and use of portland cement concrete shoulders with portland cement concrete pavement has for the most part been based on universal justification of paved shoulders combined with superior performance of the concrete as a paving material. secondary benefits such as the ability to limit water infiltration, reduction in maintenance costs, and simplified construction procedures were also taken into consideration. Recent investigations have shown that portland cement concrete shoulders can significantly contribute to the structural integrity of the mainline PCC pavement. This benefit has been quantified to show greater life expectancy for existing pavements and also to design more cost effective new concrete pavements. The research leading to substantiate the structural benefit to the mainline pavement was conducted in two phases. In 1976, field measurements were conducted on a new pavement. These measurements established the structural benefit of the concrete shoulder and provided a base line condition for further investigations to test these benefits over the design life of the pavement. In 1982, the 1976 sites were retested. The new data substantiated the findings of the original research. Using the field data from the 1982 field study and results of theoretical analysis, procedures showing the benefit of concrete shoulders in pavement design and pavement life expectancy were established.