Asphalt concrete testing device: Studying and designing based on the properties of asphalt concrete

Abstract

With the purpose of obtaining the shear strength parameters (friction angle, φ, and cohesion, c) of asphalt concretes. At the present time, almost the testing devices were designed based on the condition of the vehicle's load when they are moving on the pavement structure. That means, the fatigue resistance of the interfaces was determined through the loads acting at the interfaces between layers are repetitive mechanical action of the moving vehicles. With that view, the ratio of the normal and shear fatigue loads of asphalt concrete was not considered in terms of the nature of the material. An asphalt concrete testing device is proposed based on the modification from AST-2 instrument and Shear Fatigue Test instrument. The main parameters of this device are calculated from the ratio of shear stress and normal stress at the fatigue of the asphalt concrete according to the Mohr-Coulomb failure criterion. Test results with asphalt specimens show that the device is stable, the acting vertical loads were smaller and more stable.

Keywords: normal strength; shear stress; asphalt concrete; fatigue stresses.

Received 4 December 2018, Revised 20 December 2018, Accepted 24 January 2019