Establishing use of asphalt binder cracking tests for prevention of pavement cracking

摘要

Premature loss of serviceability due to cracking remains one of the most prominent distress modes afflicting asphalt pavements today. Although there has been significant progress in developing binder fracture tests, concerns exist about a number of the assumptions used in current analysis methods. In particular are three related main issues: (1) sorting the total failure energy into time-dependent flow and fracture energy; (2) defining the role of binder fracture in pavement cracking; and (3) selecting relevant loading rates such as to correspond to binder thermal strain during pavement cooling. This study aims to investigate and address all three of the aforementioned issues to establish the use of binder crack resistance tests as an effective tool for preventing pavement cracking. Pseudo-strain analysis showed that separation of viscous dissipation and time-independent fracture energy is unnecessary to relate binder failure energy to mixture fracture. Finite element analysis showed that even in the presence of aggregates, crack initiation in fine-aggregate mixtures is directly related to the experimentally derived binder fracture properties. Finally, multi-scale analysis was used to derive the binder strain rates in the pavement during cooling, and successfully used to develop a practical method for selection of binder fracture test loading rates that are comparable to field cooling rates and conditions.