mineral / Cementitious / Cast Concrete
Geopolymer Concrete/Low-Carbon Concrete (100mm, 125mm, 150mm, 200mm slab/panel)
Low-carbon concrete using fly ash/slag-based binders, with compressive strength classes around 20-65 MPa and at least 60% CO2 reduction reported for Zeobond E-Crete compared to OPC.
Atlas code
MIN-CEM-CC-015
At-a-glance signals
Low-carbon concrete using fly ash/slag-based binders, with compressive strength classes around 20-65 MPa and at least 60% CO2 reduction reported for Zeobond E-Crete compared to OPC.
Overview
Executive summary
Geopolymer/alkali-activated concrete uses industrial by-products such as fly ash and slag activated with alkaline solutions to form a cementitious binder. In Australia, products such as Zeobond E-Crete and UniqueCem LCC are used as lower-carbon alternatives to OPC in slabs, panels, and precast elements.
Best when…
- At least 60% CO2 reduction vs OPC (reported for Zeobond E-Crete)
- Compressive strength classes 20-65 MPa (Uniquecem LCC)
- Fire rating >4 hours reported for 150 mm slab (E-Crete)
- Uses fly ash/slag-based binders
- Lower-carbon alternative to OPC concrete
Top advantages
- 01 At least 60% CO2 reduction vs OPC (reported for Zeobond E-Crete)
- 02 Compressive strength classes 20-65 MPa (Uniquecem LCC)
- 03 Fire rating >4 hours reported for 150 mm slab (E-Crete)
- 04 Uses fly ash/slag-based binders
- 05 Lower-carbon alternative to OPC concrete
Top limitations
- 01 Limited Australian manufacturers (QLD, VIC)
- 02 Requires Performance Solution for NCC compliance
- 03 Higher initial cost than conventional concrete
- 04 Alkali handling safety requirements
- 05 Variable performance with precursor sources
Technical
Physical ·9
- Density
- 2200-2600 kg/m3 UniqueCem LCC requirements list SSD density 2200-2600 kg/m3; typical 2360 kg/m3.
- Specific gravity
- 2.2-2.6 Derived from SSD density range 2200-2600 kg/m3.
- Porosity
- 10-15% %
- Water absorption
- 5-10% %
- Hardness
- 6-7 Mohs scale
- UV resistance
- Excellent // Inorganic material
- Chemical resistance
- Excellent (except HF) // Superior to OPC
- pH tolerance
- pH 3-14
- Surface roughness
- CSP 1-3 µm
Mechanical ·7
- Tensile strength
- 4-7 MPa MPa
- Compressive strength
- 20-65 MPa UniqueCem LCC requirement for 28-day compressive strength.
- Flexural strength
- 5.5 MPa UniqueCem LCC typical 28-day flexural strength.
- Shear strength
- 3-5 MPa MPa
- Poisson's ratio
- 0.18-0.22
- Impact resistance
- Good // Research indicates improvement
- Creep resistance
- Lower than OPC // Research data
Sustainability & Health
Embodied carbon & energy ·7
- Embodied carbon
- >=60 % reduction vs OPC Zeobond E-Crete reports at least 60% embedded CO2 reduction vs OPC concrete.
- Carbon footprint
- 130-230 kg CO2e/m³ Absolute carbon footprint per m³ of geopolymer concrete varies with mix design and activator type; typical range 130-230 kg CO2e/m³ for fly ash or slag geopolymer vs ~350-400 kg CO2e/m³ for equivalent OPC concrete. This equates to approximately 55-70% reduction. Source: Turner & Collins, Construction and Building Materials 2013; Zeobond EPD data; SA TS 199:2023 commentary.
- Embodied energy
- 2.5-4.5 MJ/kg Cradle-to-gate embodied energy for fly ash/slag-based geopolymer concrete is significantly lower than OPC concrete (~5.6 MJ/kg) due to elimination of clinker calcination. Published LCA studies (Habert et al. 2011; Grant & Kenai 2020) report 2.5-4.0 MJ/kg for fly ash geopolymer and 3.0-4.5 MJ/kg for slag-based mixes, depending on alkali activator production intensity. Source: Habert et al. Cement and Concrete Research 2011; ICE Database v3.0 geopolymer entry.
- Water footprint
- 150-250 L/m³ Water consumption during batching and curing of geopolymer concrete is broadly comparable to OPC concrete (~150-200 L/m³ mix water), but curing water demand is reduced when elevated-temperature curing is used instead of moist curing. Total process water footprint approximately 150-250 L/m³ cradle-to-gate. Source: Provis & van Deventer (eds.) Geopolymers: Structure, Processing, Properties and Industrial Applications, 2009; industry estimates.
- Recycled content
- 80-100 (binder fraction) % Geopolymer binder is derived 100% from industrial by-products: fly ash (coal combustion residue) and/or ground granulated blast-furnace slag (GGBFS). Binder fraction of mix constitutes approximately 15-25% by mass; aggregate fraction may additionally include recycled concrete aggregate. Reported fly ash replacement rates for Wagners EFC and Zeobond E-Crete are 80-100% binder by-product content. Source: Wagners EFC product data; Zeobond E-Crete technical documentation.
- Renewable content
- 0 % Geopolymer concrete contains no renewable biological content. All constituents are inorganic: industrial by-product binders (fly ash, slag), alkaline activators (sodium silicate, sodium hydroxide), and mineral aggregates. Renewable content is 0% by definition. Source: Material composition analysis.
- Circular score
- 7 /10 Geopolymer concrete scores highly on circular economy principles due to 100% recycled-waste binder content (fly ash/slag diverting industrial by-products from landfill), lower embodied carbon reducing resource intensity, and full recyclability as RCA at end of life. Estimated score 7/10 reflecting strong by-product utilisation and recyclability, offset by limited disassembly potential and dependence on coal/steel industry by-product supply. Source: Green Building Council of Australia material circularity framework; Ellen MacArthur Foundation circularity indicators.
Compliance & Fire
Fire performance ·6
- Combustibility class
- Non-combustible // AS 1530.1
- Fire resistance level
- >=240 minutes Zeobond reports 150 mm slab fire rating well in excess of 4 hours.
- Ignition temp
- N/A °C // Non-combustible
- Flame spread index
- 0
- Smoke dev. index
- 0
- Heat release rate
- 0 kW/m² // Non-combustible
Cost & Lifecycle
Capex & lead time ·6
- Material cost (range)
- $280-450/m³ // 15-30% premium over OPC
- Material cost (per unit)
- $70-225/m² // Thickness dependent
- Lead time
- 2-4 weeks standard, 4-8 weeks custom // Production schedule
- Lifecycle cost
- 20% lower than OPC // 50+ year analysis
- Annual maintenance
- $0-5/m² // Minimal maintenance
- Market availability
- Limited - QLD, VIC // Regional availability
Service life & durability ·3
- Expected lifespan
- 50-100+ years // Design life
- Maintenance interval
- 10-15 years inspection // Minimal
- Warranty period
- 10-25 years // Manufacturer dependent
Layer D
Where it's used
Structural floor slabs and suspended slabs
Precast wall panels and facade elements
Marine structures and coastal infrastructure
Industrial floors requiring chemical resistance
Infrastructure projects (bridges, tunnels)
Fire-rated separating walls and floors
Thermal mass walls for passive design