S30117 Decarbonising concrete by validating the use of lower carbon cement blends for incorporation in the standards - Phase 2

This project (Phase 2 of a two-phase programme) specifically aims to investigate and validate the expanded use of lower-carbon binary and ternary blended cements by increasing the proportion of PC replacement with supplementary cementitious materials (SCMs) such as calcined clays, limestone, and other viable alternatives, through a staged laboratory experimental research and testing programme. The research will explore blend combinations and replacement levels that exceed those currently allowed under UK standards, including BS 8500:2023, the Manual of Contract Documents for Highway Works (MCHW), and the Design Manual for Roads and Bridges (DMRB).

By reducing reliance on traditional SCMs such as Ground Granulated Blast Furnace Slag (GGBS) and Fly Ash (FA), which both are subject to supply limitations, this project aims to support the wider adoption of more sustainable and readily available alternatives, including calcined clays and limestone. The project will also provide the technical evidence required to inform future updates to UK concrete standards, supported by the results of an experimental research programme. This work will build on the literature review, feasibility study, and detailed testing specification developed as part of the deliverables from the successfully completed Phase 1 of the project. This will enable the deployment of lower-carbon cement blends at scale while ensuring the durability, performance, and long-term resilience of the UK's concrete infrastructure is maintained.