Performance Prediction Models of Crumb Rubber-Modified Asphaltic Concrete

Abstract

The tyre component of solid waste is a very promising candidate for recycling, and this investigation studied the use of waste tyre crumb as partial replacement for fillers in flexible pavement wearing course. The fillers were substituted with different percentages of crumb rubber (5, 10, 20, 30, 40 and 50%). The Marshall design test was used to examine the influence of the modifier (waste tyre crumb) on the Optimum Bitumen Content (OBC), stability, flow and void properties of the asphalt concrete. The results obtained were then used to develop models to predict the performance of crumb rubber modified asphaltic concrete.Results obtained showed that partial replacement of crumb rubber up to 20% for mineral filler provided satisfactory results in terms of Stability, Flow, Void Minerals in Aggregate (VMA) and Void Filled with Asphalt (VFA) for dense graded HMA wearing course.

Keywords: Asphaltic Concrete, Crumb rubber (CR), Marshall Design, Performance Prediction Model, and Optimum Bitumen Content (OBC).