Fracture Mechanics-Based Fatigue Behavior of Jointed Concrete Pavement: Fid-Bau Portal

Fracture Mechanics-Based Fatigue Behavior of Jointed Concrete Pavement

Wei, Ya

Concrete experiences thermal and hygral deformations at early ages due to it intrinsic properties and the environmental effects. Micro-cracking results on the top surface of pavement if deformations are restrained. These micro-cracks propagate transversely and downwards over time under traffic loadings, especially during early ages. This situation can be severe if upward curling conditions exist in pavements. Estimation of the remaining fatigue life of pavements with such cracks is of significance for scheduling prompt maintenance. Conventional fatigue models established based on uncracked beam tests are no longer applicable for such cases. It is necessary to develop a fracture mechanics-based fatigue model for pavement with cracks. This study provides a new fatigue life prediction methodology for pavement with cracks. Both model prediction and experimental test results suggest that fatigue life is significantly reduced if concrete develops a partial depth crack at early ages. These results can explain the observed premature transverse cracking failure in jointed concrete pavement. Crack growth behavior can be characterized as three stages, in which the steady stage is the most important one when prompt maintenance is needed to avoid structural failure.