An existing flexible pavement that develops extensive cracks is called 

Explanation:

Alligator cracks:

• Network of interconnected cracks forming a pattern like alligator skin.

• Caused by repeated traffic loads causing fatigue failure in the pavement layers.

• Indicates loss of structural integrity in the asphalt surface or base layers.

• Often starts as small cracks and spreads over time with traffic.

• Requires major repair such as overlay or complete reconstruction.

 Additional Information

Pot hole:

• Circular or irregular holes formed on the pavement surface.

• Caused by water infiltrating through cracks, weakening the base or subgrade.

• Traffic loads cause the weakened area to collapse, forming a hole.

• Can cause damage to vehicles and increase accident risk.

• Usually repaired by cleaning and filling the hole with patching material.

Shear failure:

• Localized pavement failure due to lateral sliding or displacement under heavy loads.

• Occurs often on steep slopes or weak subgrades.

• Manifests as cracks or deformation parallel to the traffic flow.

• Can lead to rutting and surface distress.

• Requires improving subgrade strength or drainage.

Ravelling:

• Gradual loss of surface aggregates from asphalt wearing course.

• Caused by aging binder, poor mixing, or inadequate compaction during construction.

• Results in rough, porous surface with reduced skid resistance.

• Increases susceptibility to moisture damage and further deterioration.

• Often treated by seal coating or surface overlays.