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Addition of fly ash or GGBS in concrete has shown to increase the durability and thus the service life of concrete structures exposed to chlorides. Currently, the durability relies on regulations, which beside a minimum cover thickness also put constraint on amount and type of SCM in different environments. Swedish regulations do not, however, consider the actual durability of different binders. As a consequence, a LCA might be misleading. This paper investigates the climate impact of concrete with SCM in chloride environment. Current prescriptive design approach is compared with a performance based service life approach and applied to bridge parts.

s the global population is growing and changing the globalization direction towards large city areas the needs for the development of infrastructure and housing will increase. In order to have a safe and sustainable construction the infrastructure needs to be not only sustainable but also durable. In some cases, the concrete is subjected to severe environments, e.g., elevated or high temperatures, de-icing salts, seawater exposure or acidic environment, which means increased demand to extend the service life beyond what is prescribed in the design codes. The sustainability of concrete infrastructures is highly dependent on the durability. A longer service life with low repair work reduces the greenhouse gas emissions. Various admixtures and cement supplementary materials may increase the durability of the concrete. However, it is also important to consider the embodied impact and safety issues concerning innovative nanomaterials as well as application of slag and fly-ash in concrete and their future availability on the market. Here we present an overview on the latest developments on the durability and sustainability of climate-optimized concrete.

Estimates indicate that the total climate impact, from a lifecycle perspective, generated by Swedish construction processes reaches the same magnitude as emissions from all passenger cars in Sweden. A large part of the emissions from construction of roads and railways arise from production of steel and concrete used in bridges and other infrastructure structures. In this research, several cases of existing concrete bridges have been investigated. The case studies are in a very firm way analyzed, and then opportunities for reducing climate gas emissions are described and elaborated upon. Accordingly, design and dimensioning through the use of today's technology and material selection are discussed. Without developing new ways to construct bridges, or comparing concrete with other materials, a useful guide on how to use technology and opportunities that are available for constructing climate smarter versions of standard bridges today is developed and described.