Rutting prediction models for flexible pavement structures: A review of historical and recent developments

Abstract

Rutting is the major distress mode in flexible pavements occurring due to the repeated movement of traffic loading. Deformation in the pavements comprise of both recoverable (elastic) and irrecoverable (plastic) part. Overall deformation occurring in the flexible pavement system due to continuous vehicular movement is contributed from all the components of pavement. A number of empirical models have been proposed by several researchers for analysis and prediction of accumulated rutting in different components of pavement. The accumulated permanent strain has been expressed as the function of the number of load applications and deviator stress applications in most of the models proposed; however, factors such as stress state, moisture content, material type and environmental conditions also impose a significant influence on the permanent deformation characteristics of pavement materials under cyclic loading. In this article, a comprehensive review has been carried out covering every aspect of deformation related to distress occurring in pavements. Important rut models, modeling approaches and modern concepts in the rutting analysis of pavement structures have been presented. In addition to review, fallacy existing in the current design practices related to adaptation of stiffness parameters and negligence of shear strength aspect of subgrade soil has been also presented with the support of literatures. • Permanent strain along with resilient strain must be evaluated for accurate characterization of pavement materials. • Significant rut prediction models for pavement structure and subgrade soil have been discussed. • Limitation related to the adaption of stiffness parameters ( M R , CBR) in flexible pavement design.