International roughness index models for HMA overlay treatment of flexible and composite pavements

Abstract

Timely rehabilitation and preservation of pavement systems are imperative to minimising agency's costs and maximising benefits. Reasonable estimates of treatment life and pavement life extension can be made possible by developing reliable treatment performance models. Louisiana Department of Transportation and Development initiated a three-phased study to develop pavement treatment performance models in support of cost-effective selection of pavement treatment type and the time of treatment. As a result of the study, international roughness index (IRI) models for overlay treatment of composite and flexible pavements were developed. Various factors affecting the IRI of overlay treatment were identified. Climatic indices pertaining to Louisiana were developed which exhibited strong statistical significance along with the other variables as used in the IRI models. The developed IRI models provided good agreement between the measured and predicted IRI values with the majority of data within 5% of prediction error. The models could be used as a good pavement management tool for pavement maintenance and rehabilitation actions.

Keywords::

• international roughness index
• overlay treatment
• temperature index
• precipitation index
• pavement management

Acknowledgements

The authors sincerely thank the University of Louisiana at Lafayette and Louisiana Transportation Research Center (LTRC) for sponsoring this study. Special thanks are also extended to the district engineers and project review committee for their valuable feedback.

Notes

^1. Email: [email protected]

^2. Email: [email protected]

^3. Email: [email protected]