State of the asphalt industry

The Southern African Bitumen Association (Sabita) and its members are committed to best-in-class standards. IMIESA talks to Saied Solomons, CEO, Sabita, about technical developments, pavement and transportation trends.

What are the key trends shaping the future of asphalt pavements?

SS Asphalt has a history of providing value to road authorities, as well as users, and continued efforts are being made to further improve its durability. This entails better scientific understanding of the composite materials, as well as considering a mix design approach that balances the various modes of pavement distress, taking into consideration mix ageing, traffic, climate and location.

The global trend in road construction – focusing on improved project execution at lower cost through utilising digital equipment enhanced with artificial intelligence – will no doubt find fertile ground locally as well.

The advent of autonomous and electric vehicles brings with it its own exciting possibilities for accommodating the needs of this new type of mobility. While there are many futuristic scenarios being played out globally, we’ll have to sift through these and adopt what is most appropriate for our needs.

Sustainability will continue to shape our thoughts and actions as an imperative for a better future.

Is greater emphasis being placed on reclaimed asphalt?

Reclaimed asphalt is considered a valuable material source in the production of asphalt and is probably the material that is most recycled. To further this sustainability drive, much effort has gone into better understanding the optimal use of it in asphalt mixes. In 2009, Sabita funded the development of a technical guide to assist industry in its use. This document has since seen numerous revisions, with the latest 2019 version currently being reviewed to incorporate global best practice.

What are Sabita’s Technical Committees working on right now?

A permanent agenda item is the review/update of Sabita’s technical manuals. Recent and current work saw updates to Manual 35/TRH 8: Design and use of asphalt in road pavements; Manual 36: Use of Reclaimed Asphalt in the production of asphalt; Manual 38: Health and safety in construction laboratories; TG 1: The Use Of Modified Bituminous Binder In Road Construction; TG 2: A Guideline for the Design and Construction of Bitumen Emulsion and Foamed Bitumen Stabilised Materials.

To support the subcommittee focusing on material testing, the CSIR was commissioned to develop Manual 39: Laboratory testing protocols for binders and asphalt.

Currently in the making is Manual 37/TMH 5: Sampling methods for road construction materials TG3: Asphalt Reinforcement Guideline and Manual 40: Design and construction of surfacing seals. Manual 40 details the latest in surface treatments, incorporates TRH3 as well as other Sabita manuals and spans over 500 pages. The implementation of Performance Grade specifications for bitumen is also high on the agenda, with a dedicated subcommittee providing the necessary focus.

Being a member of the relevant SABS committees enables alignment of the various SANS specifications with the latest technical know-how as per the Sabita guides. As but one example, SANS 1083, which currently only covers aggregates for concrete, will in future contain specifications for use in all areas of construction (including roads).

Are current road funding models working?

In South Africa today, many people are paying more road use tax with the fuel levy than their comparative fair share of road

Saied Solomons, CEO, Sabita

use demands. They are also paying in personal time due to congestion and increased vehicle operating costs.

Many believe that the fuel levy should continue to be the answer. But with rapid urbanisation occurring the world over and South Africa being no exception, the provision of adequate capacity and the management of trunk roads in urban areas face the biggest challenge.

When the fuel levy was introduced in the early parts of the last century, the urbanisation phenomenon was hardly on the horizon. The issue then was more about connecting the various parts of South Africa. The fuel levy has played its role, but such a road pricing mechanism is woefully inadequate today to deal with real 21st century issues such as urbanisation, the imminent introduction of electric vehicles, air quality, congestion, and safety. To adequately deal with this new paradigm, a totally different approach is required.

Any new road charging system considered must be easy to understand, with greater transparency, in order to provide confidence to the road user that government’s investment in road infrastructure is in their interest.

Would it be more cost-effective to seal low-volume roads?

The answer is an overwhelming yes!

The current Draft Roads Policy for South Africa stipulates that the roads sector must: (a) satisfy citizens’ right of access to constitutionally protected basic services, and (b) maximally contribute to economic growth. If one considers just the right to have efficient and effective access to healthcare services and basic education, then the provision of all-weather surface roads become an imperative.

Many studies into this matter have concluded the same and the latest paper by Dr Matthew Townshend and Professor Don Ross, entitled ‘A road investment prioritisation model for South Africa’, once again provides well researched guidelines to tackle this challenge.

How serious is South Africa’s roads maintenance backlog?

While government estimates the backlog to be around R200 billion, new research by UCT’s Professor Don Ross and economics consultant Dr Matthew Townshend found that it is somewhat over R400 billion. The difference is largely attributed to out-ofdate government data and the extent of the country’s network considered in the backlog. The research document found the provincial road maintenance backlog to be R150 billion, while the municipal road maintenance backlog was estimated at R242 billion. The situation certainly does not bode well for the future of the road network, given that the annual allocation to roads falls short of what is required merely to maintain the network’s current standard.

How are bitumenstabilised materials evolving?

The first technical guideline on the subject published in 2002 was followed by a second version in 2009, titled A Guideline for the Design and Construction of Bitumen Emulsion and Foamed Bitumen Stabilised Materials TG2. This edition combined BSM-emulsion and BSM-foam in one document, due to the many similarities between the materials, while recognising material science differences between the two approaches.

The latest version, published in August 2020, takes into consideration data collected from thousands of kilometres of all types of road structures that have received BSM treatment over the last decade. Significant research into the behaviour and performance of BSMs has been undertaken, focusing on mix design, classifying materials for design, and structural design – all of which have been incorporated into this guideline.

How do you see the market unfolding in 2021?

The last few years have been very difficult for the road construction industry and the pandemic has added to these woes. Given the work being done by the Public-Private Growth Initiative, I am optimistic that we will see a better industry in 2021. Government procurement processes remain one of the major stumbling blocks, so solving this issue must be given priority.

SABITA’S ASPHALT ACADEMY

The Asphalt Academy offers numerous training courses on the design, use and application of bituminous materials in road construction. These NQF 5+ courses are scheduled and executed as part of the South African Road Federation training suite. Courses at level NQ4 and below are offered on demand, except for the Material Testers courses which are scheduled.

Great strides have recently been made towards the introduction of an ISO 17204 certification scheme for material testers in civil engineering laboratories. This new training scheme will kick off with a pilot run towards the end of 2020.