Compaction characteristics assessment of Hot-Mix asphalt mixture using Superpave gyratory compaction and Stribeck curve method

A compaction model of asphalt mixture combined with Stribeck curve theory was established to evaluate the contact friction behavior of compaction characteristics. The results show that the viscosity of asphalt has a linear relationship with temperature in the double logarithmic coordinate, whereas the viscosity of asphalt mastic has a good linear relationship with the temperature in the semi-logarithmic coordinate. The proposed designed compaction stage energy index DCEI can well characterize the compaction char-acteristics of asphalt mixture. When the asphalt viscosity is in the range of 200-400 mPa?s or the mastic viscosity is in the range of 1-3 Pa?s, the DCEI value shows a low peak value, which is consistent with the Stribeck curve theory. The compactability of asphalt mixture during compaction decreases firstly and then increases with viscosity of the mastic. The DCEI value also decreases firstly and then increases with the average mastic film thickness. The relationship between the viscosity/thickness of the mastic and the DCEI conforms to the trend of the Gaussian formula. When the Stribeck curve theory is applied to the compaction process of asphalt mixture, the compaction process is divided into three states: boundary lubrication, mixed lubrication and hydrodynamic lubrication. The research results help to reveal the com-paction mechanism and provide a simple mixture design method to compact easily during construction. (c) 2021 Elsevier Ltd. All rights reserved.