Project Summary
This phase of the Spark Project focuses on designing high-performance, low embodied carbon concrete mixes for next-generation precast construction. Building on the foundation laid in SPK-I, SPK-II investigates innovative binder systems combining high-volume fly ash (FA), ground granulated blast furnace slag (GGBFS), and ultrafine fly ash (UFFA), enhanced with advanced admixtures and basalt fibres. The project aims to deliver structurally robust, low-carbon concrete solutions tailored for vertical battery mould (VBM) casting systems to be used in commercial precast production. Future trials will explore nano-reinforcement using poly-functionalised graphene oxide (p-GO) to further enhance strength, durability, and sustainability.
DBI Partner
Key Outcomes:
- Designed and tested a range of ultra-low carbon concrete (ULCC) and mortar mixes using high-volume SCMs, including FA, GGBFS, and UFFA.
- Conducted comparative trials with multiple superplasticisers (SPs)—including MasterGlenium MG 8739, ACE 35, and X-Seed—which improved flowability, setting control, and hydration acceleration in low-OPC environments.
- Achieved excellent flowability in key SCC trials, with slump flows up to 550 mm and V-Funnel times between 9–20 seconds—confirming suitability for VBM-based vertical casting.
- Demonstrated early-age compressive strengths suitable for precast demoulding (e.g., 9.1 MPa after 6 hours of heat curing for HVFA60, and 53.1 MPa at 7 days for 30FA30GGBFS.
- Verified over 50% reduction in CO2 emissions compared to traditional OPC mixes, with as low as 222.7 kg CO₂/m3 in FA-rich blends under normal curing.
Impact
- Achieved >50% carbon reduction using high-volume SCM blends, supporting DBI decarbonisation goals.
- Enabled early demoulding (6–8 hrs) under heat curing, improving productivity in VBM systems.
- Promoted circular economy by utilising FA and GGBFS industrial by-products.
- Established groundwork for nano-enhancement strategy by using poly-functionalised graphene oxide (p-GO).
- Delivered scalable, low-carbon mix designs ready for commercial precast adoption.
Future work:
- Optimize ultra-low carbon nano-concrete mixes to improve strength and durability.
- Perform extensive testing to validate material performance in real-world conditions.
- Conduct prototype panel casting trials using optimized mixes in vertical battery mould systems.
- Prepare for the next phase focused on sustainable, renewable energy-powered curing technologies.
Acknowledgement
We sincerely thank Spark Projects (SPK) for their collaboration, and the Department of Infrastructure – Decarbonising the Building Industry (DBI) initiative and the University of Melbourne for their funding and support. This work contributes to a transformative roadmap for decarbonised, high-performance precast construction in Australia.