How High-performance Concrete can Aid Sustainability

Brief 

High-performance concrete can increase the sustainability of construction projects, according to an editorial published in the journal Sustainability. “Indeed, high-performance should not only be intended in terms of mechanical properties, but also in terms of durability and capacity of the materials to cope with harsh environmental exposure conditions,” the editorial states.

Insight

t is well-known that concrete is the most widely utilised construction material in the world. Therefore, any action intending to enhance sustainability of the construction industry cannot help but consider the supply chain, production, distribution demolition and eventual disposal, landfilling or recycling of this intrinsically composite material.

The use of High-Performance Concrete, although it may sound counterintuitive at first, can be one of the most effective, though technologically challenging, options to make the construction sector more sustainable. Indeed, high-performance should not only be intended in terms of mechanical properties, but also in terms of durability and capacity of the materials to cope with harsh environmental exposure conditions.

In this light, even the use of Recycled Concrete Aggregates (RCAs) in the production of Recycled Aggregate Concrete (RAC), which is generally accepted as the most realistic solution to reduce the environmental impacts of concrete productions, should guarantee a sufficiently high-performance, regardless of the origin of RCAs

[1].To this end, specific processing procedures and mix-design formulations are requested with the aim to obtain limited loss in performance when RAC is exposed to severe environmental conditions, like water immersion.

[2]. or freeze-thaw cycles

[3]..Similarly, the partial replacement of Ordinary Portland Cement (OPC), which is notoriously the most environmentally harmful among concrete constituents, with other Supplementary Cementitious Materials (SCMs) or Alternative Binders (ABs) should undergo careful research work intended at assessing the actual performance of the resulting cementitious composites.

In this respect, promising results have been obtained by considering several SCMs or ABs, such as Municipal Solid Waste Incinerator Bottom Ash [4], Belitic Calcium Sulfoaluminate Cement [5] or Steel Slag [6], the latter consisting of either ground granulated blast furnace slag (GGBFS) or unprocessed ladle furnace slag (LFS).