LCA based recommendations for the selection of eco-concretes using blast furnace slag and fly ash

The development of circular economy models for the construction sector brings important
challenges and opportunities to research and particularly to make knowledge transfer, for example through
public policies. Santiago de Cali, third major city of Colombia (South America), is developing a circular
economy model policy, which is mainly based on waste valorisation. Among others, the model includes a
family of eco-concrete products that replaces Portland cement by blast furnace slag and fly ash coming from
local industries. Therefore, the aim of this research is to develop scientific based recommendations to
stakeholders for the selection of different concrete products (i.e. beams, columns, slabs) using blast furnace
slag and fly ash (eco-concretes). Considering that life cycle assessment (LCA) is the most employed tool
for consolidating, comparing, and assessing sustainability impacts [1], the LCA of these concrete products
for the design of a sustainable residential house was performed. The LCA software Building for
Environmental and Economic Sustainability (BEES) developed by the National Institute of Standards and
Technology (NIST) was selected for the study. Results include a discussion on the environmental impacts.
Furthermore, a methodology for the selection of sustainable building materials is presented.