Spiral cracking pattern in asphalt materials
By: Behzad Behnia, William G. Buttlar, Henrique Reis
Publisher: ElsevierDownload PDF More Info
The present work for the first time reports observations and modeling to characterize three-dimensional spiral-shaped fracture patterns in a bi-axially stressed layer of asphalt material bonded to an aluminum substrate. Five different asphalt materials with different fracture characteristics are investigated. A logarithmic spiral model was found to mathematically represent the 3D helix-shaped cracks observed. A spiral tightness parameter is proposed for the characterization of spiral fracture patterns in asphalt. Results of acoustic emission and compact tension tests are also presented and employed in the evaluation of observed spiral cracks. The shape of spirals are found to be influenced by the fracture properties of the asphalt materials tested and appear to be independent of the thickness and shape of the test sample. The embrittlement temperature and fracture energy of tested asphalt materials were found to correspond to the characteristic parameters of spiral cracks.