Some types of clay have shrink – swell behaviour, called expansive clay. We found them in arid and semi-arid areas. The phenomenon of shrink – swell soil is the cause of many construction damages. It affects many countries. Solving this problem is currently a challenge for engineers. Until now, there is no universal classification to characterise this kind of soil (swelling soils). Therefore, it is necessary to find ways to better understand and deal with this phenomenon. This research master's thesis focuses on the characterisation of expansive clays. A solution to reduce the swelling effect is proposed and tested on the Tunis El Manar University’s swelling clay. This one is based on the use of a granular layer that will on the one hand reduce swelling effects and on the other hand serve to water drainage. For a ratio between the thickness of the granular layer and the swelling soil layer equal to 1, a reduction in swelling of 18.52% is observed. This study is still in progress. Indeed, we still have to find the optimal thickness of the granular layer and the optimal diameter of the grains that give us the best result.
