Rigidity of a suspension bridge is attributed to the dead load as well as the rigidity of stiffening girder (or truss). This paper deals with the theory and the structural elements of the unstiffened suspension bridge with heavy deck, the rigidity of which is given intensionally by dead load only. As examples, the test results in two of this type of bridge are discussed. It is noteworthy that this type of a suspension bridge is sometimes economical and preferable according to circumstances.

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In this paper the authors investigated experimentally on the stress distribution and the flexual rigidity of a simply supported long pipe beam containing water under several different levels.
It was ascertained that S. Timoshenko's theory is not suitable for adaption to the thin shell structure with large deformation.
The authors introduced a useful approximate formula for practical design of this kind of structure.

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In this paper, the author proposes a new method of computing the rainfall intensity formula of short duration, basing on the “Theory of Probability”, the author has named this new method “Probable rainfall intensity formula”.
Furthermore, as a result of applying the new method to the cases in the main cities in Japan, a new formula for the rainfall intensity of short duration in Japan has been derived, that is in the form; I=a/(b+√t) in which, I=rainfall intensity (mm/hr), t=duration of rainfall (5-120min) a and b=Constants.
The constants are determined on the basis of the data obtained from more than 26 cities, such as SDNDAI in TOHOKU region down to NAHA in OKINAWA Island in Japan.
This formula may be advantageously applicable to the estimation of flood discharges in small drainage areas, especially suitable for estimating the storm sewage.

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In Japan, the run-off phenomena for river basins with many available hydrological tdata have been researched from many points of view in order to contribute to the rationalization of river plannings, but the run-off analysis for river basins with only a few available hydrological data was so difficult that the satisfactory results have not been obtained so far.
In this paper, the authors first considered a method to make the imperfect hydrological data useful for river basins with relatively many available data, and furthermore analyzed the runoff phenomena for river basins with only a few available data, utilizing the results of recent hydrological researches. The results obtained here would contribute much to the rationalization of river plannings in Japan.

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The radial flow permeameter is used to define the coefficient of permeability of soil, bymeans of two dimensional seepage flow occuring horizontally throughout the soil sample, caused by making a suitable water pressure act on the porous pipe that is set in the middle of the cylindrical sample (See Fig. 1 and Phots 1 and 2).
From the testing results of this newly-built apparatus, the writers are convinced to have been able to correct some of the common faults and errors of the conventional testers that have hitherto been in use.

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This paper presents a general solution how to estimate the bearing capacity of foundation piles in the cohesionless soils and also to compute the stress distribution in the soil around piles. Theoretical calculation agrees with experimental results.

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If the principle of electro-osmosis is applied as a method of reducing skin friction between a metal wall and a mass of clay, the operation is simpler as compared with the conventional methods.
Moreover, this method is convenient, because the same equipment can be simultaneously used for not only reducing but also increasing the skin friction.
H. K. S. Ph. Begemann suggested already that this method could be succesefully applied to the pile-driving and the sinking of pite foundation.
But he did not present the mechanism of reducing skin friction, nor a possibility of effectively utilizing this method for various types of soil.
On the mechanism of decreasing skin friction, the author indicated that the electro physical effects consists of two reducing effects; the bubble effect due to electrolysis of water and the letting and accumlating effects due to development of osmotic water around the negative electrode. Futhermore, the author treated experimentally the practical application of this method to the various conditions of samples.
As a general result, it has been discovered that there is a possibility of effectively utilizing this method to the foundation work in clay soil having high adhesion.

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It is found by the author that a new soil stabilization by means of lignin materials—spent sulphite liquor or its extracts—adding potassium dichromate, aluminium sulfate or ferric chloride as the auxiliary agent is most suitable to the organo-volcanic ash soils in Japan, which cannot be well stabilized by means of Portland cement, and the effects by the new lignin method are explained from the soil engineering point of view. Next, this method is applied to the grouting into the ground as a new method, and the test results in laboratory are written, showing the promise of practical use.

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The mechanism of the electro-osmotic drainage of soil had been studied by the many engineers on the standpoint of the stationary state, but the quantitative treatment could not be in practice.
The author studied the phenomena experimentally as well as theoretically, and discovered that the mechanism of the electro-osmotic drainage of soil was explainable analogously to the mechanism of the heat conduction. So the quantitative analysis for the electro-osmotic drainage process has been possible for the clay stratum.

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In this paper, the wheel-load meter, which is tentatively made by the author and its test measurements on a street in Kobe City are described. The meter shows satisfactory function for easy measurements of wheel-load under the operational conditions of vehicles in comparatively congested traffic. Basing on both of the results obtained and the data measured in the past by another observers, the distribution characteristics of wheel-loads are discussed. Moreover, the design load of highway structures subjecting to the wheel-loads is discussed in brief.

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Although the methods of photogrammetrical surveying have made a remarkable progress in recent years, yet the methods of traditional ground surveying are necessary not only for the control points surveying of aerotriangulation and for the setting-up of the designed dimensions on the actual ground, but also especially for the geodetic precise surveying of the ground specific points.
Up to this time, among the instrumental errors of the surveying telescopes, it is the observation errors due to the deviation of cross-hairs in reticule, and their adjustment problems, that have come often into question in the civil engineering circles. But, on account of the condition of the development of the surveying instruments in Japan in those days, all the papers in the past on these subjects were concerned to the adjustments of the cross-hairs in the external focussing telescopes, not to the internal focussing telescopes, and there has never been one dealing with the functional relation between the deviation of cross-hairs and the collimation errors. However, from a geodetic precise surveying point of view, it is very important to investigate and to clarify the functional relation between the deviation of cross-hairs end the collimation errors as well as their adjustments, otherwise it would not be possible at all to perform the right adjustments of errors.
In this paper, from the above points of view, the author has analytically investigated the shape of locus of collimation points in various surveying telescopes and has clarified the functional relation between the deviation of cross-hairs and the collimation errors, and furthermore, has verified the correctness of his opinions through the indoor and outdoor experiments.

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Combining the equations of motion of fluid with the equation of continuity, the author solved numerically differential equations of flood-flow which is one kind of unsteady flows. The system of the flood-flow under consideration is nonlinear with a finite amplitude. In this paper, some characters are deduced from this method by numerical computation.

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