Circular Materials

The materials whose particle size enables them to be classified in the form of gravels or sands contribute to the granular skeleton of materials whilst the fines, after having been subjected to chemical, thermal or mechanical processing, have the potential to be used to partially replace hydraulic binders (cement, lime, etc.)

To do so, the CTP has acquired a series of equipment in order to:

• Activate fine materials to confer on them a pozzolanic or a latent hydraulic character (Siebtechnik  eccentric vibrating mill, ZOZ attritor mill, etc.
• Employ materials containing the different secondary materials (mixers, hydraulic press, gravity table, vibrating table, etc.);
• Characterize the physical parameters (VICAT setting-meter, appliances to measure consistency, the rheology, etc.) and mechanical parameters (appliances to measure the longitudinal modulus of elasticity and the shear modulus, the resistance to compression and to bending, the load-bearing capacity by means of establishing the values of CBR/IPI parameters, etc.).

Because it is a question of recycling secondary materials, the CTP is also equipped to be able to carry out leaching tests, either on monolithic blocks or on materials which have been subjected to particle-size reduction.

Generally speaking, the CTP is capable of developing numerous types of materials (inert, of a binding or structural nature) with specific properties and which are constituted of, or which incorporate waste (or by-products) to be recycled. This expertise is developed around the following aspects:

• The characterisation and the processing of different ‘ingredients’ (the production of powders, agglomerates or homogenous mixes, optimisation of the granular skeleton, the sequencing of additives, etc.);
• The understanding of the mechanisms brought into play to ensure cohesion within the material (the effect of natural or accelerated hardening, stabilisation/solidification, inerting/encapsulation, the monitoring of the reactions by calorimetry, ATG, etc.).
• The forming (pouring, pressing, pelletization, etc.) to obtain materials and their final characterisation (compression strength, leaching behaviour, etc.).