Ecoblend cements, available from Independent Cement and Lime, offer an environmentally responsible alternative to cementitious binders in concrete design.
A type GB cement conforming to AS3972, Ecoblend consists of specified proportions of Ordinary Portland Cement (GP), Ground Slag (GGBFS) and/or Fly ash. Ecoblend cement has a minimum supplementary cement material (SCM) component of 30 per cent.
Specially formulated to reduce the environmental impacts of cementitious binders used in concrete and stabilisation products, Ecoblend uses supplementary cements such as slag and fly ash to ensure a significantly lower product life cycle impact. By providing the option of using a binder with significantly less material input, energy input and emission output, Ecoblend helps create a very low embodied energy material.
Ecoblend complements these significant environmental advantages with its superior technical qualities without adverse cost implications.
Cement binders – an environmental perspective
According to Graeme Findlay (Partner) Warren and Mahoney Architects, ESD and sustainable architecture are forcing architects (and engineers) to re-evaluate the basic principles of building design. Academics around the world are claiming green buildings are healthier, more productive to occupy and cheaper to run.
Life Cycle Analysis (LCA) is used to investigate the life cycle of certain materials in terms of their environmental footprint. ISO 14040 defines standard LCA methodologies and protocols allowing consistent embodied energy comparison of materials used in construction.
LCA considers a range of environmental impacts such as resource depletion, energy and water use, greenhouse emissions and waste generation among others. Ecoblend cements perform significantly better than Ordinary Portland Cement (OPC) in all of these LCA categories.
Ecoblend reduces demand for OPC, a product derived from inherent natural resources.
Ecoblend reduces the demand requirements for the burning of fossil fuels used in the energy intensive cement clinker production.
Ecoblend use will displace approximately 700kg of CO2 emissions for each tonne of slag used as an OPC replacement.
Ecoblend uses an industrial by-product as its major blended component - Granulated Blast Furnace Slag (GBF Slag), a by-product of steel production, which would otherwise end up in landfill.
Achieving sustainable concrete design with Ecoblend
Sustainable concrete design can be achieved by reducing embodied energy in specified materials; and by increasing durability. Both criteria can be satisfied with the use of Ecoblend.
The Ecoblend LCA illustrates the reduced embodied energy associated with using slag blended cements. Equally important is the quality of construction materials, and longevity contribution to the structure.
Ecoblend 50 meets the Australian Standard AS 3972 Low Heat (LH) Special Purpose Cements. Ecoblend 65 meets AS 3972 Sulphate Resisting Cement (SR) otherwise known as Marine Grade Cement. Use of Ecoblend 30 will deliver significant durability enhancement over the use of a singular OPC.
Advantages of using Ecoblend cements
Environmental benefits of Ecoblend cements include reduced CO2 emissions; use of an industrial waste diverted from landfill; reduced demand for virgin limestone resource; energy resources saved, reducing need to burn fossil fuels; heat island effects reduced; lower embodied energy; and extended structural life.
Technical benefits of Ecoblend cements include higher ultimate strengths; increased durability with higher chloride and sulphate resistance; lower heat of hydration; enhanced workability in both concrete and stabilisation products; protection against AAR; efficient hydration at higher strengths; self compacting abilities increased; and dye and pigments more readily accepted.
Economic benefits of Ecoblend cements include longer structural life; reduced structural maintenance cost; and equivalent or lower initial and secondary cost.
- Good Environmental Choice label – ICL’s Ecoblend, Australian Builders (Type GB) and Steel Cement has achieved the Good Environmental Choice declaration, offered by Australian Environmental Labelling Association Inc (AELA).
- Ecoblend has received 3rd party accreditation to ISO 14024 ‘Environmental Product Declaration’.
- Green Building Council of Australia, ‘Greenstar – Office Design Rating Tool’: Ecoblend can be used to gain credit points under the Greenstar program.
- BDP Environment Design Guide – Pro 31 November 2003 ‘Concrete and Sustainability’
- Municipal Association of Victoria – Eco Buy program
Image: Beacon Cove Marine Works