This report refers to the determination of the Modulus of Elasticity Es in saturated of clay-silty sand mixtures. The experimental determination of Es is part of a research work, which determines the factor of strength and strain of the above material. The results of this report show the variation of Es to the changes of the mixture" s composition and also describe the situation occurring in the clay-silty sand layers of the wider area of Thessaloniki.
The rocks of Thessaloniki plain are sedimentary; they have been formatted during the Miocene, Pliocene and Pleistocene periods. At the south of the city, miocenic brackish, as well as brackish and marine formations are also reported (Demiris et. Al, 1987). The soils of the city, according to the data appear to have significant differences concerning their place and depth, it is possible to classify them especially these which are of interest for foundations and technical works, according to the following six soil formations (Tsotsos - Pitilakis 1998): SOIL A: Artificial earth fillings, originated by demolitions of various eras, mixed with natural soil material (debris). This layer has a varying thickness of 2m to 11m, and occurs not only in the old city which lies within the Byzantine city walls, but also outside of them, mainly eastward and along the coastal zone. They don"t appear to have frequent gaps and up to now they generally didn" t cause serious problems to the numerous constructions which are founded on them.
According to Skempton - Bishop (1951), "silt" is the soil material which has a WL - value < 35 and in which the percentage of the containing clay is less than 15% (Manou - Andreadis, 1992).
