Roadphalt CAS series colored overlay seal materials

Technology background
Colored asphalt concrete pavement has many great advantages in landscaping, enrichment of urban style, guidance of traffic and reduction of traffic accident, and it is not worse than ordinary asphalt pavement in performance, but it has disadvantages of material and cost. Especially, when colored asphalt pavement is used, asphalt in the asphalt mixture agings gradually under the actions of both wheel and environment, and color darkens gradually. This is mainly reflected by the fact that the binder adhesion decreases and pit, looseness and color difference appear on the pavement surface; on the other hand, if construction quality of pavement is controlled poorly and porosity is too large, pavement will be damaged in the early stage of usage. If the phenomenon is not treated promptly, performance of pavement will decrease further.
Nowadays, the field of maintenance material for colored asphalt pavement is almost blank, and it is basically in the unsupervised state after paving colored asphalt pavement, and nobody can maintain. Once pit, looseness and color difference appear on pavement surface, the only way is to expand existing problems of pavement gradually. When it reaches a certain level, re-paving after washing is costly and can not restore original surface and color.
The appearance of Roadphalt CAC series sealing material of colored overlay solves many problems such as high cost and difficult maintenance of asphalt pavement. The product is a colored silicon-modified asphalt-base fog seal material and can be sprayed on the ordinary asphalt concrete pavement directly. It has many characteristics such as low-cost material, simple construction, short construction cycle and fast traffic. It also prolongs the test period of existing asphalt pavement.
 
Product profile
Roadphalt CAS series colored overlay seal materials are silicon-modified asphalt-base fog seal materials, and they are new materials of both colored asphalt pavement construction and maintenance developed by our company and the key laboratory of traffic engineering in Tongji University. The product mainly consists of four components, namely two main ingredients and two important additives. One major component is a polymer-based material treated by special process, the other major component is an organic silicon polymer with composite active ingredient; one additive is a refined aromatic compound, and the other additive is a special surfactant with intellectual property right.
 
Mechanism
Polymer of Roadphalt CAS series colored overlay seal materials themselves have good anti-aging properties. Polymer-based composition and asphalt in the mixture are well compatible. Polymer-base composition, which has good adhesion and toughness, can seal the fine cracks in the asphalt mixture effectively.
Active organic silicon polymer of Roadphalt CAS series colored overlay seal material has high viscidity and hydrophobicity. Meanwhile, the molecular group is small and can soak into inside of asphalt material. In addition, the existence of organic silicon polymer provides bond strength and adhesion between compositions of asphalt pavement, especially aggregate, so separation and detachment of asphalt mixture reduce, and spontaneous mixture loosens because of moisture. The presence of organic silicone can significantly improve stability of asphalt pavement and performance of resistance to deformation distortion, and ensure that inside and outside of asphalt pavement are kept dry and many problems caused by the reduction of moisture. Therefore, the usage of Roadphalt CAS series colored overlay seal materials can extend the service life of asphalt pavement, and greatly reduce the cost of pavement maintenance.
Special compositions of Roadphalt CAS series colored overlay seal materials make them have the following technical characteristics:
1. Low cost: and the original asphalt pavement can be transformed into colored asphalt pavement in the premise of no structural damage of original asphalt pavement.
2. Excellent workability. The construction is very simple, and quick construction can be conducted at room temperature, about 12h-24 h after construction traffic can be opened.
3. Low viscosity. Good infiltration with asphalt mixture, and film can not be formed on asphalt pavement surface, so it soaks into the inside of mixture quickly and becomes compatible with the original asphalt.
4. Good hydrophobicity. Maintenance materials soak into asphalt pavement surface to ensure that pavement and mixture have good hydrophobic effectiveness as they contain silicone waterproofing agent,
5. Excellent anti-aging: Material property is stable in the long-term ultraviolet irradiation.
6. Excellent adhesion: The organic silicone in the composition can increase adhesion of aggregate in asphalt mixture.
7. When original colored asphalt pavement is maintained, performances of pavement and color of original colored asphalt pavement are restored.
Roadphalt CAS series colored overlay seal materials mainly have the following two purposes:
    1. They can directly be used on the ordinary black asphalt concrete pavement, and original black asphalt pavement is transformed into colored asphalt concrete pavement. In such construction of colored asphalt pavement, no transformation of original black asphalt, no mixing of asphalt, no paving equipment, no need for many workers, no requirement of lengthy pavement closure. Materials contain asphalt, and they are compatible with original asphalt pavement stably.
    2. They are high-permeability maintenance materials of asphalt pavement and contain composite active ingredient of organic silicone polymer. they belong to hydrophobic materials and can quickly penetrate into inside of colored asphalt pavement. After penetration, Firstly, minor cracks and gaps of original asphalt can be sealed. Secondly, this can improve the activity of asphalt in the asphalt concrete and increase bond strength between aggregates for prolonging the service life of asphalt pavement. Thirdly, they can restore color of colored asphalt pavement and can be implemented in the early stage of both ageing and darkness of color. So they have advantages of low cost and effective application.
Features
1. Transform black asphalt pavement into colored asphalt pavement.
2. Restore color of original colored pavement
3. Film is not formed on the pavement surface, and it will not be worn and does not affect skid resistance
4. Enhance its adhesion to paint
5. Available in cold and hot weather
6. Excellent bond strength and adhesion
7. Excellent hydrophobicity
8. Fast curing, 12-24 hours after construction traffic will be open, significantly reduce close time of construction site.
9. Simple construction at room temperature, and construction can be conducted at 0℃, but most maintenance material has high requirement for temperature.
Construction scope
Roadphalt CAS series colored overlay seal material, which is an economical and ideal material and colored protection agent of colored pavement, can be applied to a variety of asphalt pavement.
Physical properties
Specific gravity: 0.90
Color: red, green, blue, yellow, orange, etc.
Viscosity(25 ℃):<100cps
Pavement surface: asphalt
Solid content: 60%
Smoke: no
 
Construction method
1. The storage period of the materials is 2 years at room temperature.
2. When temperature of pavement surface is higher than 20 ℃, rapid construction can be conducted under all circumstances, after 12-24-hours traffic can be open, pavement surface must be dry, solid, and clean with no dust.
3. Before construction, materials will be precipitated in the processes of transport and storage, so materials are poured into new 200-liter drums and fully stirred before using.
4. Mechanical or manual brushing is used on the pavement surface directly, and the height of nozzle from ground is≤35cm. the brushing amount of 0.2-0.4 L/m is recommended, and it is related to porosity of pavement. Upper limit is selected when porosity is big, lower limit is selected when pavement is dense.
Construction process chart
1. Before construction, the original pavement is green, but fades after use.
 
2. During construction, small spray equipment is used and artificial spray can be used.
 
3. After construction, it restores the original light green (Note: If the original pavement is a black asphalt pavement, after construction it is identical to the effect)