TOL Super-tough Ultra-thin Overlay Technology (THIN Overlay, TOL) adopts TOL super-tough modifier to prepare super-tough/highly elastic asphalt mixture. It is applied to preventive maintenance of high-grade pavements and corrective maintenance for minor distresses (pitting, raveling, ruts less than 1.5 cm deep). It can also be used as surface overlay for newly built roads. Featuring skid resistance, noise reduction, drainage performance, wear resistance and environmental friendliness, it can effectively extend pavement service life, improve pavement smoothness and contrast of road markings, and enhance driving comfort.
The thickness of TOL super-tough thin overlay ranges from 1.2 to 2.5 cm. The typical thickness is 1.2 cm when paved on asphalt pavements and 1.5 cm on cement pavements. For heavy traffic, intersections and other similar conditions, the recommended typical thickness is 2.0–2.5 cm.
Figure 1 Pavement Structure and Appearance
图1 超强粘结性
2、Super-tough modified asphalt: ductile and crack-resistant. Its mixture boasts outstanding performance, good adaptability, convenient construction, high cost performance, noise reduction, drainage capability and aesthetic black pavement appearance.
二、Technical Composition
TOL super-tough additive: dosage is 8–12% by mass of asphalt.
Super-viscous tack coat: application rate is 0.2–0.25 kg/m² for cement pavements and 0.15–0.2 kg/m² for asphalt pavements.
As an asphalt functional layer, the hot-mix ultra-thin skid-resistant wearing course is only used for functional improvement and maintenance of pavements. It is not applicable to highways at all levels with structural instability. Meanwhile, due to its thin thickness, it is also not suitable for sections with severe pavement rutting.
