LAUSR

Abstract Steel slag is nowadays widely used as aggregates for asphalt pavement construction. It can minimize the environment pollution resulted from reducing natural aggregate consumption and recycling solid waste. However, there are few studies on application of steel slag in the preventive maintenance and its enhancement mechanism on surface skid resistance is still unknown. Laser scanning technic and digital analysis method were combined in this study to explore this issue. The morphology of basalt and steel slag was firstly quantified by imaging analysis and then used as fundamental backup for further explanation. Profile features of micro-surfacing samples containing steel slag were captured and studied. Meanwhile, wet track abrasion test and loaded wheel test were conducted to verify mechanical feasibility of using steel slag in the micro-surfacing. Results show that replacing basalt with steel slag could increase the positive texture significantly, due to the morphological differences between steel slag and natural aggregates. Positive texture contribution and peak profile contribution of steel slag can guide to design micro-surfacing with good skid resistance. Abrasion losses, lateral and vertical displacement are all decreased after replacing basalt with steel slag due to a stronger interlocking structure, indicating that steel slag can increase the ability of micro-surfacing to resist traffic loading.