25 Years of Driving Innovation
in Asphalt.

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.

With the advent of the new Revision Of COTO Standard Specifications For Road & Bridge Works For State Road Authorities, the onus for the submission of asphalt mix designs now lies with the contractor. A thorough and sound understanding of the principles & goals involved in the mix design procedure is required…

The pros and cons of both standard and “new age” field and laboratory permeability testing methods. The author warns that an accurate void determination method is critical to high levels of correlation, no matter which tests you choose. By Joanne Muller.

This presentation will give you the lowdown on methods for storing aggregate, techniques for moving aggregate, sampling techniques, moisture issues, and quality. The objective is to ensure consistency of material, minimising both moisture content and contamination.

Johannes Lambert covers all the bases in this detailed presentation, including the chemistry and refining of bitumen, classification and properties of bitumen binders…

A binder manufacturer discusses the impact of historic seasonal trends on availability of products and services, the characteristics of winter seal products, and issues around health, safety and the environment.