THE ASSESSMENT OF EFFECT OF INERT MATERIALS ON THE BEHAVIOR AND SHEAR STRENGTH OF FRESH AND AGED MUNICIPAL SOLID WASTES

This study were conducted to investigate the effect of inert materials of waste using large scaled triaxial tests on fresh and aged waste samples in the Kahrizak landfill of Tehran by adding aggregates with varying fracture percentages by 15\% in weight to samples. The results indicated that the presence of inert material section leads to increase in shear strength of the waste mass up to three times than the initial values and as the inert materials have more roughness and rigid surfaces, shear strength increases consequently. The impact of the inert materials on new samples is more than the older samples due to the nature of the waste components, but the shear strength of old samples under same conditions was determined to be higher up to 50\%. Also, the inert material portion have a greater effect on the increasing of the internal friction parameter (\Phi) and can increase it up to three times than the initial value.