Alternative Biomineralisation for Concrete without cement (ABioC)

The ABioC project aims at developing a biomineralisation technique using non-encapsulated cells, to improve the properties of Geopolymer Concrete (GPC) infrastructure, by reusing geopolymer precursors currently disposed in landfill as wastes. The geopolymerisation of Pyramids of Giza is an example of the durability of the technique - the binding of aluminosilicates and highly alkaline solutions holding aggregates together, not using Portland cement as a binder.

ABioC will benefit the concrete industry by enabling the incorporation of local waste materials in versatile GPCs, offering a path to decarbonisation of the construction sector. This will expand GPC's huge potential applications for infrastructures, making them more environmentally friendly. Current GPCs issues regarding shrinkage and durability.

Shrinkage can be 2-4 times higher than in Ordinary Portland Cement (OPC) concrete, chloride penetration is higher than in OPC and the pH is lower, making its use difficult with reinforcement due to corrosion. The long-term durability of GPC remains under-investigated.

Biomineralisation recently emerged as a nature-inspired approach to consolidate, repair and protect construction materials through the use of bacteria that promote calcium carbonate deposition in concrete to heal microcracks. ABioC will (O1) study the capacity of the precursors to act as carrier and protect the bacteria from a harsh environment; (O2) elucidate on the mechanisms of bacteria-mediated inhibition of GPC corrosion in structures, compared to reinforced OPC concrete and (O3) demonstrate the potential of self-healing bio-enhanced GPC to prolong the service life of infrastructure with a variety of GPC materials combinations, greatly reducing the need for costly maintenance intervention, in comparison to OPC structures.

Such interdisciplinarity, engagement with world-leading experts and stakeholders, will allow the fellow for an exceptional broadening of scientific skills and research portfolio.