Improvement Of Sandy Soil Properties By Using Bentonite

The main goal of this study is studying the improvement the engineering properties of soil mass. These properties are shear strength and maximum dry density which are effect on the foundations of the structures and their stability. The cohesionless soil can be given some cohesion by rearrangement of soil particles and decrease the voids between the particles by adding fine particles between them and decrease voids and increase the density, then the required properties can be improved. the chemical combinations due to the additives can also generate new bonded materials give the soil mass a good properties. In this study, the effect of different percentages of Bentonite which were added to the soil on the engineering properties of soil. The grain size distribution of soil sample and the classification of soil was (sandy poorly graded) according to the Unified Soil Classification. The compaction test was made for (2.5, 5, 7.5, 10)% of Bentonite. The direct shear test was made on the soil sample also for the same percentages and the shear strength parameters (C & Ø) were changed. Adding 7.5% of Bentonite to the poorly graded sandy soil gives better results than other percentages used in the present study.