Speaker
Description
Abstract. Flushed road surfacing is a large problem in Australia and New Zealand whom both rely heavily on spray (or chip) seal as a cost-effective wearing course for flexible pavements. Conventional methods for correcting flushed spray seal surfacing can comprise texture reseals or hot chip placement but most typically involves high pressure water blasting of the surface. This essentially removes the flushed/excess binder which also risks reducing the durability and moisture resistance of the seal, making the future remaining life of the surfacing uncertain. Over the last 3 years, Hiway Group has worked through an R&D process to develop a new method for the treatment of flushed seals resulting in a self-contained chip spreader integrated within high-capacity heating banks, named HiTex. HiTex is a technology for the treatment of flushed wearing courses that refines the earlier “Hot-In-Place Asphalt Recycler” (HIPAR) heating banks that were used historically to heat and soften thin asphalt surfacing before insitu recycling. Here the heating of the flushed surface allows a more controlled liquefaction of the binder allowing the sealing chip to be placed and heated for optimum adherence. The innovative process allows the restoration of the macrotexture and skid resistance properties of the wearing course, through correction of the binder/stone volumetrics within the surfacing layer without removal of any of the flushed bitumen. This ultimately improves the life of the pavement as there is less chance of water ingress through the surfacing layer when compared to water cutting. The configuration of the HiTex unit allows for selective treatment of the flushed pavement via single lane wheeltrack, both wheel tracks or where necessary full lane-width treatment.
