Concrete manufacturers claim that using substitute like blast furnace slag, fly ash and silica reduces the climate impact when used as a substitute for cement. Reducing climate emissions is an important topic for companies that currently produce concrete to achieve a sustainable society. The results have been collected by conducting interviews withexperts and sending out a questionnaire survey to concrete companies as well as some assessment through possible calculations that are linked to the survey results.

The purpose of the survey is to find out the different substitutes used in Sweden and which substitutes may be conceivable for the future and to assess the development work for these different substitutes. The study shall provide relevant information about these different substitutes and show what effects are brought to the climate when the substitutes are used. The aim of the study is to increase understanding of current and future concrete and how these various substitutes can be useful in the future in the manufacture of concrete.

Blast furnace slag, fly ash and silica are three different substitutes used as substitutes for cement. The most common substitute that is available and useful in Sweden is blast furnace slag, which means less climate impact.

Conclusions drawn by the study are that these various substitutes contribute to reduced climate impact when used with cement and that substitutes are a temporary solution, meanwhile the real problem is to find new products as alternatives to limestone in cement production.