Long-term skid resistance of high-friction surface treatment of pavement using high-alumina refractory waste

Abstract

• High-alumina refractory waste has a potential to be used as an alternative aggregate for HFST. • The skid resistance of the silicon carbide-mullite brick is above 90 % of that of calcined bauxite after long-term polishing. • The cross-scale difference of abrasion in post-use high-alumina refractories was explained. In this study, the feasibility of using high-alumina refractory waste, namely, silicon carbide-mullite brick (SMB) and refractory castable (RC), as alternative aggregates in high-friction surface treatment (HFST), was investigated. Calcined bauxite (CB) and basalt (BA) were used as control samples for the HFST. The long-term skid resistance of the HFST was characterised by conducting dynamic friction coefficient and mean profile depth (MPD) tests after long-term polishing using a three-wheel polishing device. Further, the 2nd generation of the Aggregate Imaging Measurement System (AIMS II) was used to determine the shape characteristics of the fine aggregates. The MPD and AIMS II results were combined to evaluate the contribution of the macrotexture to the skid resistance. Subsequently, the microtexture and mineral composition of the aggregate were tested. The test results indicated that the SMB is a suitable alternative aggregate in the HFST and can provide friction comparable to that of CB. Aggregates BA and RC exhibited a similar skid resistance: approximately 70 % that of CB. Furthermore, the anti-skid mechanism of the HFST was investigated based on the macro and micro textures of the aggregate. The structure of the refractory waste was an aggregate matrix, which can provide a richer macrostructure for the SMB. Moreover, the hardness difference between the mineral phases can produce abundant microtextures. The cross-scale difference of abrasion in post-use high-alumina refractories contributed to the skid resistance of the HFST. The results of this study help in realising the goal of clean and harmless utilisation of high-alumina refractory waste and reveal an alternative environmentally friendly aggregate for the preparation of the HFST at low cost and low energy.