ABSTRACT

In South America the systems most commonly used for designing pavements and analyzing their life cycle costs are based on subgrade resilient modulus. For example, performance models from the World Bank’s Highway Design and Maintenance Standards Model are based on the adjusted structural number that is obtained from the structural number of the pavement and the resilient modulus of the corresponding highway section. In existing roads, in order to calculate the expenses of major maintenance, subgrade resilient modulus is frequently obtained through FWD data back calculation, and then used in calculation software as input data for distress performance models. Likewise, during road construction, quality control data is analyzed obtained directly from LWD measurements on the subbase and the subgrade, which allows for a detailed characterization of the resilient modulus throughout granular layers construction and therefore, providing a more reliable adjusted structural number. The main experiences acquired in Chile and Peru during the implementation of this QC procedure is explained.