The Meyerhof method to estimate the ultimate bearing capacity of a continuous footing set in homogeneous ground is extended to the case of two-layered ground where the base of the footing is set in the supporting layer overlain by the weak layer. The extended method takes into account the effect of the shearing strength of the weak layer on the bearing capacity of the footing base and gives more precise bearing capacity than the method which assumes the shearing strength of the weak layer to be zero.

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Earth structures such as an embankment made artificially by compaction are in partial saturation. The shear strength of the embankment which is constructed with a constant dry density is dependent mainly on the water content. Therefore, it is necessary to investigate by experiments the influence of void ratio and degree of saturation on the shear strength of compacted soils.Three series of triaxial compression tests were performed with different drainage conditions, and the pore pressure of partially saturated soils was measured by an earth pressure gauge designed by the authors. Samples used were two kinds of "Masa"-soil (decomposed granite, sandy loam). Specimens with various void ratios and degrees of saturation were made by compaction.Test results indicate that the shearing resistance decreases and pore pressure increases with increase in the degree of saturation and void ratio. Therefore, when an embankment is constructed with the sandy soils, protection of slope and sufficient compaction are necessary.

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The consolidation is important with regard to the stability and settlement of soils compacted wet of optimum moisture content. In this paper, the problem is restricted to the consolidation of partly saturated soils compacted wet of optimum moisture content.The relation between pore pressure and total stress is obtained, assuming that the pore fluid which is a mixture of pore water and pore air is a homogeneous and compressible fluid.The consolidation equation for partly saturated soils is obtained, in which the compressibility of pore fluid, the variation of permeability with degree of saturation and effective stress, and the variation of volume change with effective stress are taken into account. It is shown from the results of numerical solution of the consolidation equation that the consolidation progresses more rapidly with increasing initial pore pressure, coefficient of volume change, and/or degree of saturation.The pore pressure during consolidation is measured, and it is observed that consolidation progresses more rapidly as the initial pore pressure, and or coefficient of volume change increase.

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