Mr. Newmark has already presented a very accurate solution of the bending theory of an incomplete composite beam simply supported. His solutions, however, vary their forms as the type of load varies, which causes many difficulties in practical application. The present author, by developing the load into a Fourier series, gave a solution of the bending problem in series. He also defined an additional coefficient of moment of inertia, and proposed a new bending theory of the incomplete composite beam which had similar forms to those of the classical beam theory, thus practically dissolving the inconvenience of Newmark's solutions. As the author's theory is only approximate, he examined the reliability of his solutions, by the comparisons with Newmark's solutions and the results of experiments.

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This paper presents certain formulas of the limit load of grillage beams and discusses the minimum weight design by using these formulas. The economical ratios of the sections of the edge beams, internal beams and cross beams are obtained against the grillage beams whose geometrical form is given. The tests were carried out on fifteen miniature models, which were made of square steel and composed of three main beams and one cross beam. The theoretical modes of collapse and the calculated limit loads almost agree with the experimental results, and from the point of view of the minimum weight design a satisfactory agreement is obtained between experiments and theoretical analysis.

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One stroke of compressive load, at the same load-speed as that caused by earthquake was given onto the concrete and mortar specimen. The relationship between stress and strain, and failure conditions were looked into, and the findings were compared with ordinary statical compressive tests.
As a result, it was found that almost linear relations existed between the dynamical strength of failure and the logarithmic value of failure time (0.03sec.-100sec.); that the shorter the failure time, the larger the strength of failure; and that compressibility in the strength of failure was almost unchanged regardless of failure time. It was also noticed that the smaller the failure time was, the steeper the stress-strain curve became, a relationship which substantiates a high degree of viscosity.
The authors have attempted to explain the dynamical behaviors of concrete and mortar approximatively by obtaining the coefficient of elasticity and coefficient of viscosity of the simple 3-element model which is composed of the Kelvin body and a spring connected directly to it.

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In this paper, the author deals with the phenomena of hydraulic jump and submerged efflux. The experimental and the theoretical work are divided into four phases, the first of which derived the equation of sequent depth from continuity and momentum equations in sloping channels. In the second phase, the wave length and the amplitude of undular jump are analysed basing on the theory of cnoidal waves and shallow water waves of infinitely small amplitude, thus interesting results are obtained from the comparison between theories and experimental results. The third phase deals with relationship between the Froude number and the Reynolds number in jet flow of the jump front for different inclinations of channel bottom, and the author finds out an opposite tendency in comparing the above case with the Froude number and the Reynolds number in uniform flow without hydraulic jump for different inclinations of channel bottom. The last phase analyses the region of submerged efflux and the limit between the hydraulic jump and the submerged efflux.

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The purpose of this paper is to describe a new method for solving complex networks of open channels, which are frequently seen in alluvial plains. A basic equation for correcting the assumed discharge is derived from Escoffier-Raytchine-Chatelain formula for back-water profiles. A simplified method based on the modified basic equation is solved by Hardy Cross method, and the general one based on the complete basic equation is solved by systems of linear algebraic equations.

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The pore water pressure in soil during the stationary electro-osmotic process in soil mass was studied with respect to the mechanism of the variation of its distribution in soil mass and also to the influence on the soil properties.
Several apparatuses for measuring the pore water pressure in soil were designed and used. The analysis of the experimental results may develop a completely different theory of the distribution of the pore water pressure during electro-osmotic process in soil as in the past.
According to this theory, the variation of the distribution of the pore water pressure was chiefly caused by the junction of pH in soil mass and the difference of the speed of electroosmosis between the right hand side and the left hand side of this zone.
The physical and mechanical soil properties was much influenced by this variation of the distribution of the pore water pressure during electro-osmotic prccess.

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This paper describes the results of experiments which were carried out with a hydraulic model to find out the lowering of the artesian pressure at the mid point between well to well and the discharge from a well by setting of the relief well system.
There were differences between these test results and the analytical conclusions and the results of electro analogical tests which had been reported by T. M. Middlebrooks and W. H. Jervis. The author's data were obtained about 25-30% on safety side in PkD/Q curve than their results.
Moreover, he suggested another two methods to raise the efficiency of the well system (setting of the partial drainage layer and utilization of relief pile), and estimated their effects basing on his model test.

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