GRAPHene enhanced pre-CAST concrete (GRAPHcast)

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Pre-cast concrete is more affordable, controllable, quicker-to-install than onsite concrete-casting and aligns with UK Govt ambition to promote off-site manufacturing/modular construction.\[1\]However, today's pre-cast concrete mixes pose numerous challenges:1\. The production of cement (concrete's binding agent) is highly-carbon-intensive (860kgCO2e/tonne)\[2\].2\. The cement content required to reach design strength gives pre-cast concrete a high carbon footprint (256-329kgCO2e/cu.m), despite using cement replacements.3\. Cement replacements retard curing/strength-development (16-hour-demoulding, 14-day safe-transport), limiting productivity and risking damage during handling/storage.4\. Steel reinforcement enhances early-age-strength but increases product-cost and embodied-carbon.Nationwide-Engineering-Research-and-Development-Ltd(NERD)'s patented Graphene-Enhanced-Concrete(GEC) admixture, CONCRETENE, has been previously developed for the ready-mixed concrete sector, where the strength-enhancing effect of graphene enables reduced cement-content, or reduced concrete-volumes compared to traditional Ordinary-Portland-Cement(OPC), or replacement-material blends (e.g.CEM-III). These material-savings deliver a significantly reduced carbon-footprint (up to 30% reduction).In addition to decarbonisation, CONCRETENE accelerates strength-development/reduces curing time (e.g. 220-Tonne CONCRETENE slab reached 28-day design strength in just 24-hours in I-UK:99366). CONCRETENE is therefore ideally suited to address the major precast sector challenges, but first needs to be reformulated to meet the more complex-chemistries and production-demands of precast vs ready-mixed.The GRAPHcast project is a collaboration between CONCRETENE developers, NERD, and Roger-Bullivant-Ltd(RBL), part of the international Vinci-Group that incorporates Soletanche-Bachy, world-leader in building-foundations, with operations in 60 countries.Alongside iterative CONCRETENE reformulation by NERD, testing, scale-up, and site-trials by RBL will assess performance in precast piles and beams for residential-buildings and low-rise structures. Finally, by validating performance on a live-construction site, GRAPHcast will pave the way for rapid commercialisation of CONCRETENE. Although precast is a smaller market than ready-mixed concrete (and therefore less attractive to private-investors), it is easier to exploit in the short-term, since sales can leverage the well-established sales-network of RBL, in contrast to relying on NERD making direct-sales to individual companies.\[1\]Construction-Playbook:https://www.gov.uk/government/publications/the-construction-playbook\[2\] ICE: https://www.ice.org.uk/media/200i0yqd/2022-04-26-low-carbon-concrete-routemap-final\_rev.pdf