This webinar presents the outcomes from a series of workshops with industry and users aimed at identifying future research needs and required changes to the Austroads Guide to Pavement Technology Part 4K: Selection and Design of Sprayed Seals. The aim of this projects was to continue refining the Austroads sprayed seal design method and its related guidance to better suit evolving traffic loads, pavement structures, and material technologies.

The Austroads sprayed seal design method, widely used in Australia, provides guidance on materials, treatment selection, and methods for calculating binder application rates and aggregate spread rates. In New Zealand, the chipsealing design method is detailed in Chipsealing in New Zealand.

Ongoing changes in traffic loadings, pavement structures and materials have prompted updates to the Guide that have been immediately implemented into a newly published version. To ensure the design methods remain reliable and that sprayed seals can perform under increased traffic volumes, updates were based on input from seal designers, transport agencies, consultants, and contractors as part of the workshops held in Australia and New Zealand. These changes, and the future research plan generated as part of this project will be described in this webinar.