Application Scenarios and Technical Requirements

The core application scenarios for high-viscosity binders focus on specialized paving areas demanding superior adhesion and durability from asphalt binders. Drainage asphalt pavements (OGFC, permeable pavements) feature an open-graded structure with abundant coarse aggregates and limited fine aggregates. The mixture's strength primarily relies on the binding action of the binder. Simultaneously, their high void content makes them more susceptible to degradation from sunlight, air, and water. This technical characteristic renders high-viscosity binders indispensable functional materials for drainage pavements.

Against the backdrop of sponge city development, the application value of high-viscosity asphalt modifiers has gained broader recognition. This material enables surface water to permeate directly for lateral drainage or infiltration into the ground, effectively replenishing groundwater resources. It also offers functions such as sound absorption and noise reduction, as well as mitigation of the urban heat island effect, providing essential material support for permeable asphalt pavement construction in sponge cities.

Major Project Applications

The steel deck paving project for the Huajiang Canyon Bridge on the Guizhou Liuzhi-Anlong Expressway—the world's tallest bridge under construction—represents a landmark application of high-viscosity, high-elasticity modified asphalt under extreme conditions. Spanning 2,890 meters across a 1,420-meter-deep mountain gorge, the bridge faces severe challenges from strong winds, high humidity, heavy rainfall, and significant diurnal temperature fluctuations, demanding exceptional pavement material performance.

The high-viscosity, high-elasticity modified asphalt custom-formulated for this project was entirely produced using Hainan Baling New Materials Co., Ltd.'s novel thermoplastic styrene-butadiene rubber (SBS) modified asphalt product specifically designed for road applications. This technology enhances the bridge deck's flexibility and fatigue resistance, prevents brittle cracking, and improves overall pavement performance. Throughout project implementation, quality control measures such as dedicated production lines and single-batch shipments ensured consistent material reprocessing stability.

Industrialization Process and Technological Breakthrough

The domestic production of high-viscosity modifiers exemplifies independent technological innovation in road materials. Originally developed in Germany, China achieved industrial breakthroughs through independent research. The high-viscosity asphalt modifier production line, jointly developed by Handan Transportation Bureau's Materials Supply Division and the Highway Research Institute under China's Ministry of Transport, served as the nation's sole facility capable of mass-producing this product. It optimized costs while maintaining equivalent construction expenses, breaking foreign technological monopolies.

Process Routes and Preparation Technologies

The application of high-viscosity agents follows two technical routes: wet and dry methods. The wet process involves pre-blending the modifier with base asphalt through shear mixing to produce high-viscosity asphalt, which is then used in mixture blending. The dry method directly adds the modifier to the mixing drum for simultaneous blending with aggregates and asphalt. Research indicates that the dry process has an optimal modifier dosage of approximately 11% by asphalt mass. At this dosage, the high-viscosity asphalt mixture produced via the dry process exhibits slightly lower serviceability than that from the wet process but still maintains good engineering applicability.

Technology Development Outlook

Current high-viscosity modified asphalt still faces practical challenges including high energy consumption during preparation, long-term performance degradation, and relatively high material costs. Future technological directions will focus on the integrated application of green modifier development, nano-reinforcement technology, and intelligent warm-mix strategies. This will drive high-viscosity binders toward low-carbon efficiency and extended service life, providing sustained momentum for the technological advancement of road engineering materials.