The first National Conference on Concrete Roads and Allied Structures, ConPaveStruc 2023, was hosted by the South African National Roads Agency (SANRAL) in Pietermaritzburg recently. The event was held as a collaborative event between Cement & Concrete SA (CCSA), the Council for Scientific and Industrial Research (CSIR), the South African Road Federation (SARF) and SANRAL.
This conference was conceived to address the significant volume and extent of concrete pavements and related structures being built. Expected outcomes were to generate more knowledge, expertise and capacity, facilitate knowledge transfer and embedment, and to generate future research needs.
A total of 16 resolutions were identified for focus and future research:
- Emerging supplementary cementitious materials, such as calcinated clays, to support energy saving and reduce CO₂ emissions.
- Achieving net zero by 2050 to be actively pursued by the sector.
- Update the COTO Standard Specifications for Road and Bridge Works for South African Road Authorities to incorporate new cement types, and review current specifications for concrete used in pavements.
- Research to be undertaken to render South Africa’s transport infrastructure more climate resilient.
- Upgrade the Department of Transport’s Technical Methods for Highways TMH 7, with respect to target reliability criteria set for serviceability of roads-related structures, focussing on target and service reliability in particular.
Hanlie Turner, business development manager of CCSA, and Bryan Perrie, chief executive officer of CCSA, pictured at ConPaveStruc 2023 in Pietermaritzburg.
- Active crack control to be investigated for implementation on continuously reinforced concrete pavements (CRCP).
- Investigate the use of alternative (recycled and/or artificial) aggregate as well as recycled concrete aggregate (RCA) crushed sand for application in concrete pavements in South Africa.
- Explore the use of RCA in other applications, such as backfills, unbound aggregate shoulders, cement-stabilised/lean concrete subbases and asphalt mixes.
- That non-technical regulations (resulting from a lack of information) preventing the reuse of RCA must be overcome by the provision of better access to information as well as technology transfer activities.
- High-quality management plans to be revisited and improved upon, and that additional tests, such as the resistivity test, should be considered for inclusion in the quality control plan.
- Vibration technologies and techniques require urgent attention.
- Development of a Technical Recommendations for Highways (TRH) guideline on tunnel design and construction to be considered.
- Further investigation into the pull-out test for assessing bond strength to improve accuracy of the method, and/or that an alternative test must be investigated.
- Improving guidance regarding moisture conditioning of the substrate surface prior to the application of a concrete overlay on pavements.
- All road restraint systems (barriers) should conform with the requirement of an appropriate standard (such as the international EN 1317).
- Hazards associated with untreated barrier ends to be mitigated.
The 25 presentations at ConPaveStruc 2023 highlighted developments in cementitious materials, showcased current projects in South Africa and presented international case studies and insights. From this, 16 resolutions were identified.
Full acknowledgement and thanks go to www.cemcon.sa.org.za for the information in this editorial.