EFFECT OF WETTING AND DRYING CYCLES ON THE PROPERTIES OF CLAYEY SOIL POLLUTED BY INDUSTRIAL WATER

Abstract

Contamination of the soil residues of various kinds, starting from sewage to industrial wastewater from the many problems that affect soil properties and their uses in general and on the engineering properties, in particular the study of the effect of these contaminants and methods of treatment effects on the soil of the priorities of researchers in this area . This thesis includes the Study of the effect of industrial waste (industrial water) on the engineering properties of the soil clay as well as the study of the effect of wetting and drying cycles on the engineering properties of the soil clay treated by industrial water, where the soil has been brought from Lylan in the province of Kirkuk. Tests have shown that the properties of the soil are medium swelling and the soil classification has been according to the Unified Classification (CL) . Soil has been treated by two types of industrial water that have been brought in from the factories of Kirkuk . For the purpose of studying the effect of wetting and drying cycles engineering properties of the treated soil, samples of treated soil by industrial water have been exposed to (12) cycle of wetting and drying cycles after the compaction of soil private templates . The results showed that moisturizing and drying cycles lead to a reduction of the value of liquidity limit by (14%) soil type (A) and (14.3%) of the soil type (B),and reduction plastic limit and plasticity index. It also increases maximum dry density and the reduction of the optimum moisture content and also increase in both the effective cohesion (C'), the effective angle of internal friction (Ф') of the soil and the unconfined compression of soil. The effect of wetting and drying cycles on the consolidation characteristics have led to a decline of the coefficient of consolidation (Cv), compression index (Cc) and swelling index (Cs). As for the swelling properties, the wetting and drying cycles lead to reduction of the swelling percentage by (29%) soil type (A) and (28.3%) of the soil type (B) and swelling pressure by (37.4%) soil type (A) and (36.4%) of the soil type (B) . Chemical tests also showed that the proportion of organic matter and the proportion of total soluble salts do not change and there is a slight reduction of the proportion of sulfates in the soil and an increase in the pH with the exposure of soil to wetting and drying cycles.