CONPAVSTRUC 2023, the recent first national conference on Concrete Roads and Allied Structures, was a collaborative event between Cement & Concrete SA (CCSA), the Council for Scientific and Industrial Research (CSIR), the SA Road Federation (SARF) and the SA National Roads Agency (Sanral), and saw more than 900 delegates registering to attend the conference online, while 120 delegates attended a parallel in-person event hosted by Sanral in Pietermaritzburg.
This conference was conceived when a gap was identified for a single platform to address the significant volume and extent of concrete pavements and related structures being built, particularly by Sanral. Expected outcomes were to generate more knowledge, expertise, and capacity, to facilitate knowledge transfer and embedment, and to generate future research needs.
During his keynote address, engineering services executive for Sanral, Louw Kannemeyer, outlined the roads agency’s commitment to ensure a safe and world-class road network for South Africa within the context of national and local challenges. CEO of Gift of the Givers, Dr Imtiaz Sooliman, urged the delegates to “claim ownership of our country and to address the issues within our sphere of expertise to ensure better living conditions for all”.
The 25 presentations at ConPaveStruc 2023, focusing on the themes of Chemistry for Cement & Concrete, Pavements, Structures, Tunnels and Barriers, highlighted developments in cementitious materials, showcased current projects in South Africa, and presented international case studies and insights.
Most importantly, 15 resolutions were identified for focus and future research:
- That further research be undertaken on emerging supplementary cementitious materials, such as calcinated clays, to support energy saving and reduce CO2
- That achieving net-zero by 2050 be actively pursued by the sector.
- That the COTO Standard Specifications for Road and Bridge Works for SA Road Authorities be updated to incorporate new cement types, whilst also allowing for a review of current specifications for concrete used in pavements.
- That research be undertaken to render South Africa’s transport infrastructure more climate resilient.
- That, with respect to target reliability criteria set for serviceability of roads-related structures, the Department of Transport’s Technical Methods for Highways TMH 7 be upgraded, focusing on target and service reliability, in particular.
- That active crack control be further investigated for implementation on Continuously Reinforced Concrete Pavements (CRCP).
- That the use of alternative (recycled and/or artificial) aggregate as well as Recycled Concrete Aggregate (RCA) crushed sand be investigated for application in concrete pavements in South Africa.
- That the use of RCA in other applications, such as backfills, unbound aggregate shoulders, cement-stabilised/lean concrete subbases and asphalt mixes be further explored.
- That non-technical regulations (resulting from lack of information) preventing the reuse of RCA be overcome by the provision of better access to information as well as technology transfer activities.
- That quality management plans be revisited and improved upon, and that additional tests, such as the resistivity test, be considered for inclusion in the quality control plan.
- That vibration technologies and techniques require urgent attention.
- That the development of a Technical Recommendations for Highways (TRH) guideline on tunnel design and construction be considered.
- That the pull-out test for assessing bond strength be further investigated to improve accuracy of the method, and/or that an alternative test be investigated.
- That improved guidance be provided regarding moisture conditioning of the substrate surface prior to the application of a concrete overlay on pavements.
- That all road restraint systems (barriers) should conform to the requirement of an appropriate standard (such as the international EN 1317).
- That hazards associated with untreated barrier ends be mitigated.
The four industry bodies will prioritise critical resolutions for short-term research and application, and deliberate long-term goals for ConPaveStruc as a catalyst for research to practical implementation of best practices in South Africa.