Research review on the Key Technology of Preventive Maintenance: The Durability of 4.75mm NMAS Stone Mastic Asphalt (SMA-5) Ultra-thin Overlay

Abstract

SMA-5 Ultra-thin Overlay is a kind of preventive maintenance material which has the advantages of fast construction, good surface texture depth, cost-effective and environmentally friendly. It is also suitable for the maintenance of bridge and tunnel which have restriction on elevation. However, the insufficient durability is the key factor which restricts the development of SMA-5. This article summarizes the key technology to enhance the durability of SMA-5 in terms of its material composition, grading and mixture design methods, which provide a reference for improving the durability of SMA-5 and promoting the application of SMA-5.