The study reported herein is concerned with the investigation of the influence of electrolyte concentration on inferential testing of clays, with a wide difference in their charge deficiencies. Commercially pure kaolinite and montmorillonite clays are used in this study. Calcium hydroxide, calcium chloride, sodium chloride and sodium oxalate are the reagents used in this testing programme. This study shows that electrolyte concentration in terms of cation factor 'f' (an index of the extent to which base exchange capacity is satisfied) enables one to better study the influence of clay composition and type of exchangeable cation on the inferential soil testing, from which mechanical properties of clay-water-electrolyte systems are inferred.

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The main purpose of this investigation is to find various factors which influence the magnitude of side friction between a soil specimen and the container wall of the one-dimensional consolidation test, and to set up suitable assumptions on which fundamental equations of the one-dimensional consolidation process affected by side friction may be derived. The factors investigated herein are as follows : Loading history, trimming effect, displacement rates, displacement, degree of consolidation, physical properties of soils, and specimen size.

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This paper deals with the theoretical part of the investigations of the effect of side friction on the process of the one-dimensional consolidation.On the basis of the characteristics of the frictional resistance and the compressibility of soils, three kinds of fundamental equations are derived and numerically solved. From the view point of the routine methods for determining the coefficient of consolidation and volume compressibility, it is indicated clearly that the side friction has completely opposite effects on the time rate and the amount of settlement depending on the relation between the void ratio and consolidation pressure, and that the characteristics of the one-dimensional consolidation affected by side friction can be classified into four categories by the characteristics of compressibility and friction of soils.

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This paper presents the results of field investigations at the places where sand volcanoes were formed and eruption of water and soil was observed during Mino-Owari, Tohnankai and Fukui earthquakes. The soil strata which were presumed to have liquefied were identified on the basis of previous studies and compared with the observed phenomena during the earthquakes. The results indicate that the eruption of water and soil during the earthquakes was not necessarily associated with a complete liquefaction of sand of the type observed during the Niigata earthquake of 1964. The Seismic intensities during the earthquakes were from V to VI according to the Japanese Meterological Agency Intensity Scale, and most of the liquefaction of the saturated sand occurred under the following conditions : The soil was coarse grained in accordance with the unified classification system, having the 50% size of less than 2.0 mm and the uniformity coefficient of less than 10. The effective overburden pressure was less than 2.0 kg./cm², the relative density was less than 75% and no fine grained soil strata lay above the saturated sand. Also presented are microscopic photographs of sands which are presumed to have liquefied.

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