偏心荷重をうける単純支持円板の曲げの問題をモーメント荷重をうける場合もふくめて一般的に取り扱ったもので, 方法として双極座標を用いる。解は級数解となるが, その係数を求める方法をのべ, 代表的な荷重位置について計算結果を示した。また, モーメント荷重をうける場合の解については特に荷重点のたわみ角について検討した。

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ある不規則な変動, たとえば風速や煙の濃度などを観測するとき, これらの瞬間最大値が観測時間の長短や記録計器の感度の良否によって異なることはよく知られている。
一方, 不規則変動のいろいろな性質はRiceの雑音理論にまとめられている。観測時間の長短や記録計器の感度は, もともとの不規則変動に周波数フィルターをかけてスペクトルを変形させることに相当する。これらの理論から瞬間最大値と観測時間・評価時間の関係を導きうる。
不規則変動でそのスペクトルの性質がわりに知られており, 実際上重要なものに風の乱れ (息) がある。半理論的に突風スペクトルを導き, これをDavenportの経験式と対比しながら2, 3の実測値と比較した。
また, Davenport式および新しく導かれた式を使って突風率と評価時間との関係を計算し, 実測とくらべた。さらに, 突風率が種々の因子でどのように変化するかを計算し図示した。
最後に, 理論と実測とを対比して突風率の実用計算式および図表を与えた。この関係式は, 観測時間・評価時間の他に高さ・基準風速・地表粗度等の因子もふくんだ簡単な式型となっている。

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Physical interpretation is given based on the linear viscoelastic theory to the wellknown fact that the modulus of deformation of some materials is greater for the rapid application of load than for slow loading. The principle for this understanding leads to the determination of the viscoelastic constants in accordance with the time of loading employed in the test.
The constants thus determined are used to describe the creep or relaxation curve as a means of representing these physical characteristics. Constitutive equations between stress and strain at any specific time of loading are developed that can be applied to analyse the test result obtained at a constant rate of stressing or at a constant rate of straining. Since the rapid transient test can be performed at considerably small time of loading, it may be justified to replace the high frequency vibration test by the transient testing method. The principle of choosing simplified model is suggested to make it easy to use it in the stress analysis problems. A comprehensive amount of the transient test data for concrete and soil having been reported. in many papers was brought together to analyse them by the use of the proposed method. The results of the analysis are presented in the form of creep curve.

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The quantitative estimation of damping effect is necessitated, when the dynamic response of a structure to such a time-dependent external force as gusty wind, earthquake, or rolling stock on it, is to be obtained. However, it is said impossible to estimate the overall damping of a structure theoretically and one is forced to know it empirically. The present paper is concerned with the damping of bridge superstructure within its elastic range, and consists of the following three parts to contribute the above-mentioned requirement. The authors should like to place special emphasis on Part III in which many data of the logarithmic decrements measured so far with the actual bridge structures in Japan and other countries, were collected and analyzed.

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(I) Generally speaking, almost all phenomena we treat accompany with time variations about the mean value. In connection with this, it is well known that the instantaneous peak values observed are affected by length of both sampling time and evaluation time or by the sensitivity of instruments.

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Bending of a circular plate simple supported along its edge and loaded at an arbitral point by a force or a couple is treated in this paper by employing bipolar coordinates. The problem of a circular plate subjected to an eccentric load has been discussed in various manner, since Clebsch obtained a series solution in polar coordinates of this problem. But the case of simply supported edge is more complicated than that of clamped edge and also these discussions were restricted to the case of a concentrated force. In this paper, a series solution for the case of a concentrated force in bipolar coordinates is first derived, and then it is seen that solutions for both cases of a bending and a twisting couple can be expressed in modified forms of the first solution.

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