New Activation Routes for Early Strength Development of Granulated Blast Furnace Slag

ended

ActiSlag global objective is to define efficient activation routes based on a two-step process to produce a “second generation GGBS” (Ground Granulated Blast Furnace Slag) which will be assessed in formulations for concrete or dry-mix mortar. The target is to reach 80% GGBS addition in cement while keeping the specifications of CEM II (20% of classical GGBS). Such products will be more than welcome by construction material players having to combine improved environmental footprint, competitive costs and better quality concretes and mortars. After implementation of project results and opening of new markets and products, steel producers will thus become more independent from the main GBS customers (cement makers). Prices will not be pressured anymore by cement makers and marketing diversification will become more flexible. Thus, ActiSlag will strengthen the competitiveness of EU steelmaking industry by reducing the market pressure and by increasing the value of this ironmaking by-product material. This study will be supported by fundamental investigations to further understand slag multi-scale structural organization, reactivity and behavior during early strength development which remains problematic with standard GGBS. We aim to overcome this drawback by finding the best combination of upstream (slag chemical composition, structural organization) and downstream modification (chemical activation system, curing temperature, GGBS fineness) routes. The key findings will enable to validate the concepts and define the scope of a pilot project. The gained experience also allows improving the quality of existing slag based products.