Seal Coat
Bitumen Emulsion for seal coat
The asphalt surface of the roads can experience erosion, raveling, loss of aggregate,honeycombing, and sulphate attacks over time due to weather conditions such as frost, sunlight, heat, and also road salting, snow removal, as well as the effects of excessive loading and friction, especially caused by tire chains and snowplow blades. Failing to repair and install overlay asphalt in due time will allow damages to expand, leading to complete destruction of the road surface and even the underlying layers. The use of protective layers is recommended to prevent intensification of asphalt wear out, postpone overlay installation, maintain the existing conditions, and fill the cracks.
In addition to providing a suitable road surface, these layers will waterproof it and prevent the destruction of asphalt and its underlying layers. This is a cheap maintenance method that will ensure uninterrupted and secure operation of the roads. Different methods are recommended based on the degree of destruction, the weight and volume of traffic, and type of asphalt. These methods are inexpensive and can be employed early after or even before the beginning of asphalt pavement distress.
Spraying bitumen emulsion with a layer of gravel atop it. Emulsions with longer breaking time should be used for seal coating. In addition to creating a desirable surface, seal coating can provide suitable friction properties and waterproof the asphalt. Seal coat can be used at any times, and for different degrees of pavement distress, however, a layer of fog seal is recommended before seal coating. The best temperature for applying a seal coat is the warm or hot weather. Humid and cold weather will increase the drying time needed before the traffic is allowed to pass, which in warm weather will take four hours at most. In terms of function, depending on climatic conditions and the volume of traffic, seal coated road will take up to six hours to be ready for operation. Sealcoating is recommended for low-traffic rural and secondary roads, and not for high-traffic main roads.
Applying a layer of bitumen emulsion and adding one layer of aggregates on it. Normally CRS is used for this purpose.
Seal Coat applications and facts:
- It makes asphalt layer smooth, safe, steady, waterproof and stops being slippery.
- It creates the color contrast between main road and shoulder of the road.
- Seal Coat provides more tolerance for the top layer so that the layer stands indent and ice pick tires better.
- Seal Coat lifetime is between 3 to 5 years and it is better to be applied on a warm day.
- Seal Coat is cheaper than keeping and maintaining a deteriorated asphalt layer.
- Applying bitumen emulsion as seal coat is more economical than cutback bitumen.
- Seal Coating is also suitable for the roads which we do not decide to rehabilitate.
Cationic Bitucoat Emulsified Bitumen (Seal Coat)
Bitucoat emulsion (Seal coat) is used as waterproofing coverage on asphaltic surfaces. This is used as one of the protective asphalt methods. Also for maintenance and reforming appearance form of asphaltic pavement through creating a uniform and black layer. Bitucoat emulsion will decrease weathering pace of asphaltic pavement and it is one of durability increasing methods. Bitucoat is produced in different types of CSS-1, SS-1h, SS-l, CSS-1h. crushed sand is used the amount of 0.5 to 0.8kg after Bitucoat emulsion spread in order to increase the durability of the asphaltic layer which would be damaged through heat and traffic and also to increase friction in some cases, sand is spread in the opposite angle of the first distribution to completely supply uniformity and waterproofing coverage.
Inappropriate spreading of Bitucoat emulsion will cause bitumen corrosion which leads to make the surface slipping and create the hazardous condition, especially in the rainy weather. Also, improper spreading of material or water steam pressure from soffit will cause stripping and infiltration of bitumen into the surface. Therefore, Bitucoat emulsion with bitumen percentage, cohesion promoters and proper breakage along with precise calculation of spreading range of emulsion and material will increase asphaltic pavement durability. Produced Bitucoat emulsion of the company has been used in the road network of the country such as Qom and Isfahan provinces in the past years.
