Utilização do processamento digital de imagens para caracterização de material fresado

Abstract

It is established on pavement engineering that aggregate shape properties are related to the main asphalt pavement distresses. Among the various aggregates that can be used in asphalt mixtures, the recycled asphalt pavement (RAP) material can be mentioned as an important source to replace natural aggregates, which are becoming rare. The present study investigates the influence of asphalt milling on shape characteristics of the RAP materials by using digital image processing (DIP) techniques. The materials investigated were obtained by milling a pavement urban section located in Fortaleza-CE, by using scarification techniques, and also changing the configuration of the milling machine: at 23% and at 46% of the equipment’s maximum speed (30m/min). The milled materials were also analyzed before and after the asphalt cement (AC) extraction. The analyses were performed by using the Aggregate Imaging Measurement System (AIMS). This equipment was developed to analyze form, angularity and surface texture properties of aggregates through image techniques. The results were then compared in order to verify the changes on the aggregates’ shape parameters and the influence of the milling speed on the production of these materials. In relation to the particles’ shape properties, the milling speed did not have a great influence on the parameters analyzed, even when compared to the scarified material. The presence of AC had a greater effect most on the RAP properties of surface texture, resulting on values that were less than the half for the aggregates after the extraction.