This is a report of theoretical and experimental research on the settlement and the bearing capacity of pile. A formula concerning the settlement of a friction pile is introduced with the theory deduced from a rheological standpoint. Then applying the formula, a new measuring method of the critical bearing capacity of pile is derived. The bearing capacity thus derived well agrees with the results of pile tests both in laboratory and field. This method is known to be applicable not only to the friction pile but also to other types of pile supported in soil.

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Photoelastic method for determination of stress in powder mass is applied to several problems in soil mechanics and foundation engineering.Stress distribution in the powder mass in a direct single-shear box is observed and discussed; stress distribution caused by two piles and stress distribution under a footing are observed.From these observations, it is confirmed that this method is very useful for investigation of some problems in soil mechanics and foundation engineering.

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This paper presents results of tests made to determine the mechanical properties of compacted soils under transient loads. The tests were made on soils of three types, clay, loam and sandy loam of various moisture contents and compacted densities. Increase in the ultimate strength of compacted soils was observed as the loading rate increased, that is so-called strain-rate effect, but there also were such cases that the ultimate strength in the normal static tests was higher than that in the transient load tests, according to soil types or conditions of moisture content. The changes in modulus of deformation and the effects of compacted densities on the ultimate strength are also presented.

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In this paper, the bearing capacity of a slope of cohesionless soil under the load acting upon its horizontal top or berm is obtained. The process is similar to the cases of horizontal ground, reported previously by one of the authors.The authors also assume in the present case that at the instant of failure a wedge of active earth pressure would appear directly below the load. A region of passive earth pressure along the slope can be determined as a function of the angle of slope and the angle of internal friction of soil.The transition region between the above-said two parts is divided into a number of small wedges. For these wedges the equilibrium condition of force is applied successively and at the same time the sliding surface is drawn by taking into account the sliding condition, the stress components being found by means of Mohr's circle. And thus the bearing capacity can be determined.

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A five-storied hospital building with basement was constructed on soft clayey deposits. Based on the results of soil exploration, the raft foundation was placed on compressible clay pre-consolidated by vertical sand drains and well-points. The excavation for the basement was performed successfully and the building showed practically no differential settlement after it had been completed. The paper presents a brief summary of the technical report on the design and construction of the foundation of that hospital building.

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