Determining the geotechnical properties of clay contaminated by heavy metals and salts

DETERMINING THE GEOTECNICAL PROPERTIES OF CLAYS CONTAMINATED BY HEAVY METALS AND SALTS Tayfun ŞENGÜL Civil Engineering, Master Thesis, 2003 Supervisor: Assist. Prof. Yücel GÜNEY SUMMARY The leakage waters of house and industrial wastes change the geotechnichal properties of impervious landfill clay liners. Determining these changes is important for geotechnical engineering. Because; the damages that could happen on these impervious landfill liners as a result of chemical pullution might have negative affect on environment and human health. In this study, experiments were made for determining the changes in geotechnichal, physico-chemical and micro structural properties of landfill liners. For this purpose, mixtures of Na-Bentonite and Kaolen clays were used to simulate landfill liners, for contaminatents the metalic solutions of PbCl2, CuCl2, ZnCl2, salty solutions of NaCl, CaCl2, KC1, asidic solution of HC1, basic solition of NaOH, and the water used to decompose the boron mine which contains B203 were used. Na Bentonite and Kaolen mixtures were polluted with these solutions and consolidation, free swell, consistency limits, unconflned compression, electrical conductivity, pH tests and scanning electron microscopy analysis were carried out. Experimental results of polluted Na-Bentonite/Kaolen mixtures showed decreases in shear strength, liquid and plastic limit values where as showed increases in permeability. Scanning microscopy analysis showed microstructural corruptions. Keywords: Landfill Liner, Geotechnical Properties, Kaolen, Chemical Pollution, Micro Structure, Na-Bentonite.