Application of low-carbon concrete

More Information

Products/Technical solution, Technologies and Building systems

DESCRIPTION:

Low-carbon concrete with 40% lower embodied emissions than the current standard has effectively been applied in the Voldsløkka demo site in Oslo. The low-carbon concrete class A7 used in Voldsløkka has a carbon footprint of 220-240 kg/m3, depending on use, compared to typical concrete has an emission-factor of 400-410 kg/m3. Concrete was used in the parts of the building adjacent to the ground.

BUSINESS ROUTE

Target Users

Architects, Constructors, Material providers, Research community

VALUE

Besides water, concrete is the highest consumed material in the world. It is used to produce and build the vast majority of the world’s buildings, bridges, roads, dams, and several other constructions. Cement production alone is responsible for approximately 8% of the worlds CO² emissions. Given the widespread use of concrete as a building material, the replacement of only a small fraction of the total amount of concrete used worldwide can cause significant CO2 emission reductions. The emissions related to building with concrete come, to a very large degree, from the production of the cement (as the critical ingredient in concrete) and has a large potential for emissions reduction. In addition, construction techniques and optimisation can reduce emissions, sipmly by reducing the material used.

APPLICATION

In the Voldsløkka school concrete was used in critical parts of the structure, replacing it with wooden structures in other parts of the building load-bearing structure. In general, there are several technical challenges associated with concrete where high amounts of cement are replaced by supplementary cementitious materials (SCMs). With reduced cement content and increasing amounts of other additions, the early strength as well as the long-term strength development can be reduced. Some durability properties might be also reduced. Resistance to alkali silica reactions as well as chloride ingresscan however be increased for properly cured concrete with low carbon binders. On the other hand, resistance to carbonation in buildings and frost-salt scaling in infrastructure concrete may decrease and remains a challenge. High replacement of cement with SCMs in low carbon concrete can also affect the workability (flow properties) and handling of the concrete.