Comparative Evaluation of Asphalt Concrete Aggregates Structure in the Superpave System and SCRB Specifications

Abstract

The superpave system provides requirements for the structure of aggregates in the asphalt concrete mixture, such requirements consist of gradation of aggregates and some physical properties to accomplish the target density and voids content through compaction process. However, the state commision of roads and bridges of Iraq (SCRB) also provides some major requirements for asphalt concrete aggregates structure for various pavement layers. The present assessment evaluates and compare the requirements of the asphalt concrete aggregates structure between the two methods. A comprehensive review of the aggregates structure issue is presented in this work. It can be revealed that the dense gradation of aggregates for preparation of asphalt concrete is implimented in both systems, and the gradation curve of SCRB matches the 0.45 line of superpave with its control points.