Water – Main Cause of Road Damage

Water - It's Damaging Effect.

Water is the most damaging factors responsible for premature failure of bituminous pavements. The various mechanisms by which water affects the pavements are:-

• Water form a thin, invisible film around the aggregate in the form of moisture during road construction. This obstructs the complete, strong coating of aggregate by bitumen. Therefore, when the initial bond itself is weak, the pavement is unable to take normal stress and disintegrates
• In post construction period, when water intrudes the surface of the pavement and penetrates between aggregate and bitumen film, it starts the process of stripping the binder from the aggregate.
• Pore pressure, which is the increased pressure caused by the circulation of trapped water through the void structure of aggregate also initiates stripping. The water may be present due to ground water ingress or surface intrusion.
• Hydraulic scouring which occurs on surface courses because of a compression tension cycle caused by the interaction of tire pressure with surface water