Durable Low Carbon Reinforced Concrete for Challenging Environments (DULCET)

The cost of repairs due to chloride and carbonation-induced reinforcement corrosion/premature deterioration of concrete structures made with conventional cements and mild steel reinforcement is very large. The impacts of cement manufacture on global CO2 emissions are significant (approx. 8% of global emission). There is thus a strong demand from owners of concrete assets (eg Environment Agency, Highways Authorities) to specify lower carbon concretes whilst addressing concerns a risk averse/conservative construction industry. Alkali Activated Cementitious Materials (AACMs) can offer 80% savings in embodied CO2 but limited understanding of the protection they offer to corrosion of steel reinforcement in aggressive service environments (such as marine or highways) is limiting their market growth. Cemfree (manufactured by an SME with strong ambitions to grow) is a leading UK AACM.

DULCET will develop/prove a new Cemfree reinforced concrete range for use in aggressive chloride environments (from saline coastal water and highway de-icing) where reinforcement corrosion is effectively "designed-out" through combining with a non-corroding composite reinforcement (based on basalt fibre) instead of steel. This will accelerate adoption of Cemfree AACM in aggressive environments and wider markets for reinforced concrete as there is no need to worry about reinforcement corrosion (or to wait until completion of complicated long-duration research to develop guidance for AACMs to ensure protection of steel from corrosion). The new basalt fibre reinforcement also offers 40% carbon savings on conventional reinforcement, weight savings and is recyclable at end-of-life. DULCET will enable the basalt reinforcement market to grow, address barriers and bring economies of scale to manufacturers.

The project will address issues/concerns such as the bond of Cemfree to the innovative reinforcement, develop generic concrete component designs, rebar layouts, assess buildability on construction sites and prove durability and engineering performance of the reinforced components.