Science & materials

Over the past 20 years, Lafarge has spearheaded the development of a scientific approach to building materials, aimed at understanding their behaviour at different scales and optimizing their performance. This has been made possible by new techniques and instruments such as nuclear magnetic resonance, scanning or transmission electron microscopy or nanoindentation.

With today's sophisticated technology, Lafarge researchers can study the structure of materials down to the nano-scale, in other words, at an infinitely small scale*. This has given them a greater understanding of the mechanisms which determine their mechanical strength, durability etc. allowing them to develop better-structured products with considerably improved properties.

* Nano-scale : (10^-9)

Fresh concrete can be too firm and viscous, making it hard to work with. This is because the cement particles, which act as the ‘glue' in concrete, are attracted to each other upon contact with water.

Superplasticizers developed by Lafarge researchers make it possible to enhance the fluidity of concrete without adding water. These molecules physically separate the cement particles by neutralizing their force of attraction. Consequently, the concrete remains fluid for over 2 hours and is easier to use, more resistant and longer lasting.

See superplasticizers at work in this close-up video.

Water which does not evaporate while concrete is setting creates porosities. These can result in cracks and reduce the strength of the finished material. Lafarge researchers have developed a technique known as granular packing, a process which improves the compactness and resistance of concrete by reducing porosity. This works by replacing part of the water conventionally used to make concrete with fine and ultrafine grains that occupy any spaces between the larger grains.

The result is a more fluid concrete which is more compact when it sets. As the smaller pores can better resist weathering influences, such as water, air and CO2, granular packing makes it possible to increase the mechanical strength and durability of concrete.

See how it works on video!

At the core of a piece of plasterboard is a hardened liquid paste composed of gypsum, water and additional elements, such as admixtures and foam.

The most delicate stage in the production of a piece of plasterboard is the mixing of the foam and the gypsum paste. The bubbles in the foam tend to merge together, in a process called coalescence. The mixture sets around the remaining air bubbles, giving rise to irregularities in the structure and an uneven distribution of air. The result is a very heterogeneous plasterboard core with reduced technical properties.

Lafarge's scientists have studied the interactions between gypsum paste and foam throughout the production cycle. They have perfected sophisticated techniques which make it possible to control the size, spacing and distribution of the air bubbles. The result is important savings of water and energy throughout the plasterboard production cycles, and plasterboard formulations which offer a wide range of different properties.

Discover the technological advances made by Lafarge's researchers!