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This paper presents an application of a coupled hydromechanical formulation for compacted and rockfill materials to simulate the construction and impoundment of a zoned earth dam. The constitutive relation used to model the mechanical behavior of the shoulder, filter and core materials is the Barcelona Basic Model for unsaturated materials. The hydraulic behavior of dam materials requires the specification of their water retention characteristics and their permeabilities, which will be expressed as a function of porosity and degree of saturation. The model was used in the design stage of Lechago’s dam (Teruel, Spain), currently under construction. Soil parameters were obtained by laboratory tests performed on materials to be used in the dam. The step-by-step construction (following the sequence construction of nine horizontal layers, besides the downstream preloading layers) and subsequent impounding of the reservoir was simulated in a prediction exercise, which will be hopefully confronted with actual construction measurements in the near future. A parametric study was also performed to evaluate the effects of the compaction water content of the core material on the behavior of the dam. [ABSTRACT FROM AUTHOR]

In this work, oedometer tests were used to examine the effects of ethanol-gasoline blends on the consolidation characteristics of a kaolinitic soil from northwestern Spain. As the fraction of ethanol in blends increases, the equivalent liquid limit of soil decreases, showing a dividing point for blends containing about 85% of ethanol. By means of a database of compression indexes of remolded clayey soils mixed with differing kinds of alcohol and petroleum hydrocarbon contaminants, a multivariable model for estimating the compression index of the contaminated soil is presented, on the basis of the virgin compression index, normalized liquid limit, and normalized pore fluid viscosity. The model is valid only for percentages of active clays up to 10-15% in weight in kaolinitic soil. The authors would like to encourage others to further validate and refine the approach, which may be useful for preliminary estimation of the compression index of contaminated soils, reducing operators' risk of inhaling vapors released by the ethanol-gasoline blends while performing the test and also reducing damage to conventional oedometer equipment. [ABSTRACT FROM AUTHOR]