Technical Introduction
TOL-5 Cold-mix Wearing Course is a new preventive maintenance technology, in which cold-mixed asphalt mixture is paved onto the existing pavement by a mixing-type sealing vehicle. It combines the advantages of hot-mix thin overlay and microsurfacing technologies, with a paving thickness of 0.8–1.5 cm. Through special gradation design and strict raw material control, it overcomes the drawbacks of conventional microsurfacing such as high noise and insufficient skid resistance, achieving low noise and long durability with a pavement service life of more than 3–5 years. It is suitable for maintenance of pavements with pitting, raveling, cracks and light rutting, and improves riding comfort. It serves as a green, reliable, economical and eco-friendly preventive maintenance solution.
Integrating the technical concepts of hot-mix thin overlay and microsurfacing
Core Technology
- Special and critical gradation design
Adopt gradation and asphalt-aggregate ratio control similar to hot-mix asphalt mixture to realize low noise and high durability.
- Ultra-high-performance mixing-type emulsified asphalt
The formula of special emulsified asphalt is optimized for high temperature and heavy load, ensuring excellent mixing performance and rapid curing, with traffic opening available within 1–2 hours.
- Self-developed clean stone powder
To address the common problems of insufficient sand equivalent and shortage of raw materials for stone powder, processing equipment is deployed for customized production of clean stone powder. It ensures uniform coating of aggregates and extends pavement service life.
- Outstanding performance of low noise and high skid resistance
Small-size aggregate design is adopted to avoid point contact between coarse aggregates, delivering low noise and favorable skid resistance.
- Reduced construction cost
The cost is reduced by 30–40% compared with preventive maintenance technologies such as hot-mix thin overlay and in-situ hot recycling.
Technical Standard
- TOL-5 High-performance Modified Emulsified Asphalt
- Aggregates
Technical Requirements for Fine Aggregates of TOL-5 Cold-mix Wearing Course
For preventive maintenance of expressways, national and provincial trunk highways, and urban expressways (pavement thickness: 0.8–1.5 cm):
1. Preventive maintenance of high-grade pavements on expressways and urban expressways
2. Surface repair of cement bridge decks and asphalt bridge decks with constant load requirements
3. Corrective maintenance for slight pavement distresses (rut depth ＜1 cm)
4. Pavements requiring improved skid resistance and noise reduction
