International Roughness Index and a New Solution for Its Calculation

Abstract

The international roughness index (IRI) has been one of most widely used indicators for characterizing road roughness. However, there are some issues such as the key description of IRI spread over two large reports, no detailed derivation process of the calculation of IRI, and the incomplete standard procedures for computing IRI values. To solve these problems, the computational process of IRI is derived in a time domain, and a new method for computing IRI based on the precise integration method (PIM) is proposed. Compared with standard codes, the proposed method is more efficient and more stable.