Measurement of pavement unevenness and evaluation through the IRI parameter – An overview.

Smoother pavement provides a comfortable, safe and economical riding experience to the public and prolongs the life of the pavement with low maintenance costs. Hence, obtaining a smooth pavement is considered a necessity by many transportation agencies around the world. In order to achieve a smooth pavement, smoothness specifications are developed. Smoothness specifications mainly consist of four parts: smoothness measuring equipment, smoothness indices and analysis method, acceptance limits, and incentive/disincentive payment schemes. This paper summarizes smoothness specifications in the United States and various countries around the world and provide an overview on the comparison of smoothness measurement. The smoothness measuring devices, indices, limits and payment schemes vary from country-to-country International Roughness Index is the most used smoothness index in the US and around the world. Inertial profilers are used to measure the pavement profile for smoothness. [ABSTRACT FROM AUTHOR]