It is well known that concrete deteriorates over time due to poor durability and lack of proactive maintenance. This is particularly relevant for concrete used in the road network where it is usually subjected to very harsh environment, including freeze-thaw cycles and deicing salts, as well as excessive traffic and poor ground conditions. This project will build on the existing knowledge-based within Highways England of the performance of concrete roads. This will include design, materials, damage and inspection and maintenance information. The project will then explore the suitability and performance of a range of low carbon concrete materials. The project will test standard and non-standard concrete mixes. These will include a subset of standard low carbon and novel low carbon mixes. This generally involves the use of supplementary cementitious materials in blended cements as well alkali-activated or geopolymer cements. In addition to the cement, the project can explore low carbon aggregates (e.g. Lytag and expanded clays). To address future damage and reduce or eliminate it, the project can explore the recent developments Professor Al-Tabbaa's team has produced in Cambridge on self-healing materials. This includes microcapsules (with sodium silicate repair agents in them), super absorbent polymers (as air entraining to reduce freeze-thaw damage) and smart aggregates (impregnated with healing agents) as well as a range of expansive mineral additives to prevent thermal and other shrinkage cracking.
The remit of the project will be refined between the three parties over the next few months.