Block Cracking
 
  • Blocks are interconnected cracks that divide the pavement into approximately rectangular pieces.
  • The blocks may range in size from approximately 1 by 1 ft. (.3 by .3 m) to 10 by 10 ft (3 by 3m). Block cracking usually indicates that the asphalt has hardened significantly.
  • Block cracking normally occurs over a large proportion of pavement area, but sometimes will occur only in non-traffic areas.
  • Block cracking is measured in square feet of surface area. It usually occurs at one severity level in a given pattern section;
 
Low Severity Block Cracking
  • Low: Blocks are defined by low severity longitudinal and transverse cracks
    • The majority of the cracks are about 1/4 (6mm) in width. The majority of the cracks are about 1/4 (6mm) in width.
     
    Medium Severity Block Cracking
    • Medium: Blocks are defined by medium severity longitudinal and transverse cracks
    The majority of the cracks are about 1/2 to 3/4 in (12-18 mm)wide. The majority of the cracks are about 1/2 to 3/4 in (12-18 mm)wide.
       
    The majority of the cracks are greater than 3/4 to 2 in (12-50mm) wide. The majority of the cracks are 1/2 to 2 1/2 in (12-62 mm)wide
     

    High Severity Block Cracking

    • High: Blocks are defined by high severity longitudinal and transverse cracking
     

    Many of the cracks are surrounded with medium severity random cracking.