1. The concepts of cold recycling and hot recycling of asphalt
Asphalt cold regeneration is to recycle and regenerate the worn and aged asphalt pavement in depth on site to change its original pavement structure, physical properties and chemical properties, thereby prolonging the service life of the road and reducing environmental pollution. It is an effective way to save natural resources. Hot recycling refers to the thermal recovery of old asphalt and mixing with new asphalt in the process of making asphalt mixture to make composite materials with the same properties.
2. The difference between cold recycling and hot recycling of asphalt
(1) The process is different: Asphalt cold recycling is to recycle old pavement on site, add additives and then mix it to form a new road structure. Hot recycling, on the other hand, takes place at the production site, where old asphalt is thermally recovered and remixed into new mix material.
(2) The cost is different: the cost of asphalt cold regeneration is lower than that of hot regeneration, because it can be carried out on site, and the investment in fixed assets and equipment is less.
(3) Different applicable scenarios: cold asphalt recycling is suitable for situations where the road surface is aging and severely damaged but does not require deep repair; while hot recycling is suitable for situations where the road surface damage is minor and only surface repair is required.
(4) The forms of recycled materials are different: cold asphalt recycling recycles the original asphalt on the road surface; while hot recycling recycles asphalt materials and residues cut by vehicles.
3. Advantages and disadvantages
(1) Advantages of asphalt cold recycling: it can be carried out on site, which reduces the cost and time of road construction, and has a good environmental protection effect. Disadvantages: High requirements for road materials, on some seriously damaged roads, the performance of asphalt mixture is difficult to guarantee.
(2) Advantages of hot recycling: using modern technology, the quality of asphalt mixture is excellent and its performance is stable. Disadvantages: higher cost, requiring special recycling and production equipment.
To sum up, both cold recycling and hot recycling of asphalt have their value, and both play a positive role in improving road performance, protecting the environment and saving resources. According to different road conditions and engineering requirements, different regeneration methods can be reasonably selected to complete road repair and construction.