Water is on of 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
The above-mentioned problems of poor aggregate properties, water damage etc. can be checked most effectively and economically by the use of Anti stripping compounds, specifically SUPER-BOND XS . Across the globe, be it Europe, Australia or the Americas, Anti Stripping compounds are being commonly used for improving the pavement performance.
• Minimizes the stripping value of aggregate . This enables the use of a wider range of aggregate which otherwise are unfit for road construction.
• Its use results in a complete, strong bond formation between aggregate and binder at the time of construction
• In post construction period, it helps in minimizing the damaging effect of water.
• It lowers the surface tension of the binder, thus facilitating uniform coating of aggregate. Furthermore, it improves
• the distribution and suspension of filler in the mix.
• It substantially increases the road life(25% and above) and reduces the maintenance requirement of the pavement.
• It displaces water from the aggregate and helps the bitumen to even stick to wet aggregates. This facilitates increasing the working season
• It improves as well as retains the wet strength of bituminous mix.
Super-Bond XS : Product & It's Working
SUPER-BOND XS has long chain organic amines of relatively high molecular weight. It has an amine head attached to a long hydrocarbon chain. The amine head has the property to attach firmly to the aggregate, While the hydrocarbon chain (Which is hydrophobic and of the bitumen family) attaches itself to the binder. This results in the bridging of the hydrophilic aggregate and hydrophobic binder by Super-Bonds XS, and the formation of a complete, strong bond.
Function of anti-stripping agent based on fatty amine