Function investigation of stone mastic asphalt (SMA) mixture partly containing basic oxygen furnace (BOF) slag

Aims: In this paper, the effect of the size gradations of basic oxygen furnace (BOF) slag on the functional performances of stone mastic asphalt (SMA) mixture including skid and deformation resistances was investigated. Methods: The industrially produced BOF slag coarse aggregates (BSCA) with size gradations of 4.75-9.5 mm and 9.5-16 mm were used. SMA mixtures were designed according to Marshall procedure. British pendulum number (BPN), indicating the skid resistance of asphalt mixture, was measured by a British pendulum skid resistance device. Flow number (F-N) and Marshall quotient (MQ), reflecting the deformation resistance of asphalt mixture, were determined, respectively, based on the results of dynamic creep test and Marshall test (stability and flow value). Results: showed that BSCA with a size gradation of 9.5-16 mm performed better in improving the skid and deformation resistance of SMA mixture than BSCA with a size gradation of 4.75-9.5 mm. Furthermore, BSCA with combined size gradations, namely, 4.75-16 mm, worked the best. Conclusions: These conclusions would benefit the future extensive utilization of BSCA in asphalt pavement.