The Fracture Characteristics Analysis of the Asphalt Mixtures by Virtual Loading Test

Abstract

In recent years, with the development of Digital Image Processing Techniques and Computer Science, the numerical simulation analysis on asphalt mixtures’ fracture characteristics has gradually become the focus of domestic and international scholars. However, during the analysis processing, most researchers took asphalt mixtures as a kind of linear elastic materials, which is incompatible with the visco-elastic mechanism of asphalt mixtures. Thus, it will not fundamentally evaluate the fracture characteristics of asphalt mixture. Based on this, considering the visco-elastic mechanism of asphalt mixtures, the paper makes a numerical simulation analysis on asphalt mixtures via a virtual loading of the notched semi-circular bending (SCB) testing, aiming to obtain the fracture characteristics of asphalt mixtures. This study emphatically investigated the effects of the different relative factors between the loading location and the pre-cracking on the fracture characteristics of the asphalt mixtures evaluated by J-integral method. The research shows that, there existed significant region of stress concentration near the crack tip; Under the same loadings, the longer distance deviated from the midline of the SCB specimen, the less possibility to induce fracture cracking. In other words, the longer distance deviated from the midline of the SCB specimen, the greater loadings is needed to complete its total fracture cracking process.