Objective of Al²Sibuild

Geopolymers (GP) and alkali activated materials (AAM) are mineral materials that offer a low-energy, low-CO2 alternative to conventional Portland cement-based concretes, whose competitiveness is jeopardized by increasingly stringent environmental requirements.

​

However, the raw or secondary materials generally employed to formulate these materials are not extracted locally in our region and their quality or purity is generally too high in relation to the requirements for concrete used in the construction sector. The main reason for this high quality is that, at present, these materials (e.g. silica sands, sodium carbonate, kaolin, sodium silicate) are also produced for industries other than construction, such as the food industry, water treatment, paper mills and the glass industry, whose requirements are very high.

​

This results in higher production costs (quality requirements), an increased environmental footprint (transport) and low availability of deposits (scarcity). The resulting reduction in the economic competitiveness of GP and AAM solutions slows down their implementation as substitutes for conventional cement.

​

Less pure or alternative raw materials of sufficient quality can be extracted locally in various forms (activatable clays, quarry fines, biomass or incineration ash, dredging sludge, construction waste) and are widely available in the FWVL Interreg region. The source of the raw material will be prospected following the strategy of choosing by preference alternative materials in comparison to mainstream raw material used in this domain.

​

The AlSiBuild project aims to map the region's available resources and propose examples of ready-to-use recipes and processes that can be implemented by companies in the construction sector. Pilot and laboratory-scale demonstrators will be made available to prove their suitability for concrete applications. All of this will be communicated to a broad target group.

​

The originality of the AlSiBuild approach lies mainly in the use of real, available resources to produce the materials required for the applications. These real resources are generally made up of mixed materials, which sometimes must be assembled with others to achieve usable and effective mineral and chemical compositions.

​

The project aims to get a head start on a promising sector currently under development, and to encourage its implementation by providing solutions to supply problems and economic difficulties. The production processes of these new materials might be different of the traditional concrete and good practices should be communicated to the sector to give them the opportunity to implement the new material with a high degree of confidence.

​

The local approach will help secure supply chains in the face of current climatic and geopolitical changes. The cross-border approach allows diversification of available resources and the possibility of obtaining materials with the highest functional and environmental performance. The exchange and distribution of skills across the FWVL region also helps to secure supply chains and skills.

​

What's more, the proposed materials use a different chemistry to that currently in use and offer advantages such as enhanced resistance to fire and chemical degradation. They can also offer excellent mechanical resistance in the first few hours of use, which is a considerable advantage in cases of repair or emergency intervention.

​

It is important to notice that contrary to traditional concretes, these materials also avoid the need to use sea sands, whose exploitation exacerbates coastal erosion and accelerates the impact of rising oceans.