Calibration of Performance Models for Surface Treatment to Chilean Conditions: The HDM-4 Case

The HDM-4 (Highway Development Management) model used for pavement management activities must be adjusted to the specific conditions of a country or region where they are to be used by adjusting certain calibration factors. The results obtained from calibrating the cracking, raveling, potholing, rut depth, and roughness models contemplated in HDM-4 version 1.1 for surface treatments are presented and compared with the results obtained from equivalent models of HDM-III. In this task, the “windows” methodology was used, which consists of reconstructing the distress performance curve of a specific road category starting with observation of the condition of different roads with similar characteristics (such as traffic, pavement structural capacity, and climatic conditions) but of different ages. On the basis of the results obtained, recommendations for calibrating the performance models are proposed, and calibration factors more adequate for characteristics specific to Chilean surface treatments are established. On comparing the results of the calibrated models of HDM-III and HDM-4, it is concluded that both cases furnish similar values, and use of HDM-4 models is recommended because of their operating advantages and because they afford a greater flexibility, which allows them to more aptly adapt to a broader number of cases and situations.