Study on pavement performance of steel slag asphalt mixture based on surface treatment

Steel slag (SS) as aggregate has excellent mechanical properties and rich surface morphology. However, its high water absorption and subsequent volume expansion are the main problems in the application of steel slag. Therefore, this work compares the treatment effects of cement paste (CP), silane coupling agent (SCA), polyvinyl alcohol (PVA) and epoxy acrylic organic-silicone resin (EAOR) on the surface of steel slag. The micro morphology before and after treatment was evaluated by environmental scanning electron microscope (ESEM) and Matlab modeling. The results showed that EAOR retained the profile height characteristics of steel slag, making the surface of steel slag more smooth. The treatment methods were measuring by water absorption and crushing value. The results showed that among the four treatment methods, EAOR modified steel slag (EAORSS) had the best surface treatment effect, the recommended portion of the solution of EAOR: xylene is 2:1. Finally, the pavement performance before and after steel slag surface treatment is compared. The dynamic stability and freeze-thaw resistance durability of EAORSS are slightly improved, the low-temperature trabecular bending test value does not change significantly, and the volume expansion is significantly reduced. Finally, an asphalt mixture with EAORSS is placed on an experimental road section under real conditions as an application case of this technology.