How do you predict and, critically, prevent asphalt pavement failure due to moisture sensitivity? Our specialist presenters will provide solutions...

NOTIFICATION OF ANNUAL GENERAL MEETING

This post is only viewable by logged in members. In terms of Section 6 of the Constitution of the Society, you are hereby advised that the 28th Annual General Meeting of the Society for Asphalt Technology will be held via a Zoom meeting on Wednesday 19th May 2021.

SAT is pleased to introduce the 5th edition of Sabita’s Manual 5. This revision takes account of recent developments in...

Cutting edge technology and products are employed in the bituminous surfacing of South Africa’s roads. The industry prides itself on being up to date with the latest local and global wisdom in surfacing treatments. As practitioners it is up to each one of us to ensure that our knowledge remains relevant. To this end, the Society for Asphalt Technology has invited some of the country’s leading experts to unpack the latest guidelines on surface seals & Sabita Manual 40.

Asphalt (AC) in the 21st Century is very different from asphalt made 100 years ago. With binder modification, sophisticated aggregate crushing techniques, a plethora of additives and the introduction of nano technology, asphalt (AC) has rapidly  become a “super-construction material”.

Georges Mturi points out that about 30% of bitumen used in asphalt in South Africa is modified. In this paper he discusses the context, typical additives used, guidelines and specifications, as well as selection and classification of additives. In addition to performance, Georges explores aspects such as storage, expertise required, availability of base binders and modifier, shelf life, blending and quality control. His rule of thumb – use locally available aggregate and bitumen sources and only use additives where normal binders are limited in performance.

Aggregate properties need to be clearly defined in terms of both specification and testing to ensure compliance. To support this, Ray Bonser reviews the relevant specifications including historic factors, the introduction of COLTO 1998, the Aspasa Exclusion Clauses, the current SANS 1083:2018 Edition 2.6 specification and proposed revisions to SANS 1083.

Nico shares Roadlab’s expertise in this field, starting with tests currently used to determine material properties before treatment/stabilization/modification, followed by the properties of Nano Modified Emulsion (NME) treated materials together with testing technologies and procedures.

Ensure that the project mix materialises on site by sticking to some basic principles. This presentation enlarges on the basics such as quality control of mixes containing reclaimed asphalt (RA), consistency of RA fractions in the mix, aspects to consider at stockpiles, moisture content, and finally sampling, testing and acceptance control as for conventional asphalt mixes.