Comportement Mecanique D’un Sol Expansif Stabilise Par Ajout De Sable De Dune

This study has been conducted on three types of soils extracted from the region of Laghouat in the south of Algeria, where damages has been recorded (damage of structure, cracking and partial destruction of road pavements). In the first stage the swelling of soils is estimated using indirect methods based on the geotechnical characteristics than the swelling parameters are measured, thereafter the measurement of different compoenents of suction ( total and matriciel ) is realised. The second stage of this investigation is concerned with the study of the effect of dune sand addition on the swelling potential of soils. Sand addition leads to a substantial reduction in the swelling parameters. By the end, a study of stabilized soil strength is achieved at different state of saturation. The results show that an increase of soil strenght with percentage of sand addition.