Utilization of large amounts of industrial wastes to improve sustainability of the construction sector

The concept of "sustainability" in the construction sector has increasingly led to the manufacturing of thermal comfort products composed of natural or recycled materials. Several such products are readily available in the market while others are still in the early stages of production or under research. The assessment of the sustainability potential of building materials as well as of entire buildings or structures is a significantly complex issue as it involves the quantification of three interacting and interdependent parameters: the environmental impact, the technical performance, and the lifetime. From this it is decidedly apparent that simply protecting the environmental impact (e.g., during the construction process) will not benefit the environment as long as an equivalent technical performance and lifetime cannot be ensured. This situation can be analysed using the definition of the so-called "sustainability potential". To this end, bottom ash and marble dust were used as a replacement for cement (up to 70%). In this study, technical performance of the laboratory-produced composites was evaluated using mechanical and durability tests. The sustainability potential of the composites was also analysed using the reduction in cost and the reduction in carbon dioxide emissions of the produced composites. The test results showed that the pure cement paste composites are adequate for targeting controlled low strength and non-load-bearing elements in civil engineering works. Durability performance also proved that the composites are moderately resistant to sulphates.