This paper studies the ground motion amplification coefficient Gs is introduced in the calculation method of response and limit strength, whose calculation procedure is very complex. First, the approximate formulas of Gs, which are given by the impedance ratio of the linear soil, has been proposed. The formulas can be applicable also to the actual soil although those have been developed for idealized two-layer soil conditions. Next, it pointed out that the Gs may be underestimated depending on determination of the depth of engineering bedrock for the actual soil. Finally, two kinds of methods for the determination of the depth has been proposed so that Gs might not be underestimated.

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最近の新薬は効果も優れているが,一方,副作用発現にも十分注意する必要がある.また,薬物についても注意が求められる.そんな中で,薬剤による常用量での致死的な副作用発現は何としても回避しなくてはならない.心室性頻拍,不整脈,心停止といった突然死, β2刺激薬の吸入剤による喘息死,その他,薬剤アレルギーや全身痙攣といった副作用は予測が困難であるが故に,日頃の予防対策としての観察,教育,指導が極めて重要となる.

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Creep-fatlgue tests were conducted using 316FR stainless steel at 650°C in air under a variety of strain time programs including symmetric continuous, unsymmetric continuous and strain hold cycles. By comparison of the results with test data obtained in vacuum, it was found that the life reduction which occurred for a slow tension-fast compression strain wave and the tensile strain holding wave was smaller in air than in vacuum, and that the symmetric continuous cycle gave the largest life reduction from the data obtained in vacuum. Following the creep-fatigue tests, fracture surfaces were investigated by SEM. When time/rate-dependent life reduction occurred, the fracture mode in vacuum was intergranular, but in air, striations were observed and integranular fracture was rarely observed.

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ビスフェノールF系エポキシ樹脂に界面反応法で合成した多孔質壁中空球形シリカ粒子 (多孔質シリカ粒子) を充てんした複合体を合成し, 充てん粒子の表面積, 細孔径及び吸着水が複合体の力学的, 熱的性質に与える影響を動的粘弾性, 熱的特性 (線膨脹率, DSC), 曲げ強さ, 衝撃強さを測定することによって調べた. その結果, 動的粘弾性及びDSC測定により求めたガラス転移点T_gは多孔質シリカ粒子の吸着水の増加とともに低下した. これは吸着水がエポキシ樹脂硬化剤ヘキサヒドロ無水フタル酸の能力を低下させ, 充てん粒子表面付近のエポキシ樹脂の硬化が不十分になったためと考えられた. 貯蔵弾性率及びT_g以上での熱膨脹係数は多孔質シリカ粒子の半径約4nm以上の細孔の表面積への依存性を示し, 表面積が増加すると, 貯蔵弾性率は増大, T_g以上での熱膨脹係数は減少した. このことより, エポキシ樹脂と力学的に有効な細孔の半径は, 約4nm以上であると推定された.

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A series of creep-fatigue tests were carried out using 316 FR steel at 650°C in a very high vacuum environment of 0.1 μPa under loading conditions of sequential changes from creep-fatigue loading to fatigue loading and vice versa in order to examine the accumulation behavior of creep, fatigue and creep-fatigue damages with respect to a strain cycle. The linear summation of life fraction is smaller than unity in the case of creep-fatigue loading followed by subsequent creep-fatigue loading. However, the deviation from unity is not very large for this material. A sequential change between slow-fast creepfatigue loading and fatigue loading gives a summation of life ratios less than unity. On the other hand in the case of a tensile strain hold-time cycle, the summation of life ratios exceeds unity. Other tests have been conducted to simulate creep-fatigue behavior when the material is subjected to a safe shutdown earthquake (SSE). In this case the creep-fatigue life reduction is not very large.

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A series of creep-fatigue tests were conducted using 316FR steel at 650°C in a very high vacuum environment of 0.1μPa. The test results indicate a creep-fatigue behavior which is completely free from the environmental effect of the air. In general, creep-fatigue life reduction occurs when the tension time is longer than the compression time. After the creep-fatigue tests, the fracture surfaces were investigated using a SEM. A good correlation exists between the creep-fatigue life and the fracture mode. When the fracture mode was predominantly transgranular, no life reduction occurred. On the contrary, when it was predominantly intergranular, a significant life reduction was observed. The overstress was experimentally investigated and the relation between the overstress and the inelastic strain rate was obtained. The creep-fatigue life evalution model based on the overstress was applied and it was shown that it predicts the life accurately.

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It is well known that the soil-structure interaction affects the seismic behavior of buildings. So it is important to consider the effects in the seismic design of buildings, especially those of low- and medium-rise because their natural frequency is comparatively high. But there is a problem how to estimate the frequency dependent impedance in the time history response analysis. In this paper, the validity of the time history response analysis using the transferred impulse response is confirmed. Then, comparing to the method, the validity and the characteristics of the estimation methods of constant soil springs was studied.

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In this paper, we propose an effective energy input to a structure considering soil-structure interaction, by applying the energy balance theory. Evaluated energy input to a structure of a soil-structure coupled model compared with a base-fixed model can be expressed by an aspect ratio and a period of structure and an S-wave velocity of soil. And it was examined how to evaluate the energy input to the structure for the structural design, from the view of the performance of buildings against seismic loads (ex. load-carrying capacity, ductility capacity).

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A series of creep-fatigue tests was conducted with Modified 9Cr-1Mo steel at 600°C in 0. 1 mPa vacuum to assess the accumulation of creep-fatigue damage. In these tests, each test specimen was subjected to prior creep-fatigue loading followed by subsequent fatigue loading or prior fatigue loading followed by subsequent creep-fatigue loading. The linear summation of cumulative damage of fatigue and creep life fraction was smaller than unity for the former case, and larger than unity for the latter case. The damage model based on the overstress concept was applied to the test results to verify its applicability. The accuracy of the life evaluation was not enough because of the nonlinear interaction between creep and fatigue.

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