بررسي ارتباط بين خصوصيات ذاتي تحكيم پذيري خاك هاي ريزدانه بازسازي شده و طبيعي منطقه جنوب تهران

Study the Relationship between Intrinsic Compression Characteristics of Reconstituted and Intact Fine Grained Soils for South of Tehran Region

The compressibility characteristics of reconstituted clays are used as a basic frame for interpreting the corresponding characteristics of natural sedimentary clays. Intrinsic properties are especially used for reconstituted soil which, are independent of natural state. Void index is a parameter which relates the reconstituted parameters of different clay soils. Burland 1990 suggested that the natural properties of clay soil may be different from that of reconstituted ones due to the influence of soil microscopic and macroscopic texture (fabric and bonding). In this research, clay specimens from Tehran region were prepared by water to 1.5 times the liquid limit and then reconstituted. The amount of additional water depends upon the clay content and the development of adsorbed water (diffuse double layer). Plotting the results in Burlandʹs framework, show the SCL lies well below the ICL. This is related to the rates and modes of deposition of alluvium when, a freshet (high water) from wide valleys of Alborz Mountain spread out the flood plain providing deposits of low to insensitive clay soil. In this study the compressibility parameters were correlated as an aid to site investigation interpretation.