Tailing dams could store hundreds, thousands or millions of cubic meters of tailings result of the mining extractive industry. Mechanical behavior of this man-made soil should be known in order to maintain a safe storage. Dykes rise up to form the dams and they are buildup with the same tailing material especially in the upstream method using the coarse part. The study uses oedometer classical test to determine the load effect over tailing coarse particles. Tailings are site specific and so its characteristics. It is necessary to understand the tailings degradations to achieve safe impounds. The study comprises four samples of one range-size tailing particles (e.g. 1-0.5, 0.5-0.25, 0.25-0.125, 0.125-0.063mm) subject to vertical load in traditional oedometers. Vertical load effects are measured using two dimensional image analysis and sieving. Results show that 0.063mm sample is the only one that has change in shape with low breakage (<1%) while the rest of the sizes have no shape change but high breakage is present especially in fraction 0.5mm. Settlements also are more pronounced in coarse fractions 0.5 and 0.25mm.