What does "fatigue cracking" in asphalt pavements signify?

Fatigue cracking in asphalt pavements is primarily a result of repeated loading and stress applied to the surface over time. This process is common in areas where there is frequent traffic, as vehicles create repetitive strains on the pavement. As the asphalt material undergoes these cycles of stress, micro-cracks can begin to form within the pavement structure, and if the staining continues, these cracks can propagate and lead to larger cracks, often resembling a series of interconnected lines.

The presence of fatigue cracking suggests that the asphalt is unable to withstand the repeated loads it receives, indicating potential structural issues or inadequate design for the anticipated traffic loads. Understanding this phenomenon is crucial for maintenance planning, as it often necessitates rehabilitation efforts to restore the pavement's integrity and performance. Recognizing fatigue cracking as a sign of cumulative stress helps engineers to implement timely repairs, enhancing the lifespan of the pavement and maintaining safety for users.