General reports on the damages to public civil engineering works caused by the great earthquake

付録６２

Fully Metal-Coated Scanning Near-Field Optical Microscopy Probes with Spiral Corrugations for Superfocusing under Arbitrarily Oriented Linearly Polarised Excitation

We study the effect of a spiral corrugation on the outer surface of a fully metal-coated scanning near-field optical microscopy (SNOM) probe using the finite element method. The introduction of a novel form of asymmetry, devoid of any preferential spatial direction and covering the whole angular range of the originally axisymmetric tip, allows attaining strong field localization for a linearly polarised mode with arbitrary orientation. Compared to previously proposed asymmetric structures which require linearly polarised excitation properly oriented with respect to the asymmetry, such a configuration enables significant simplification in mode injection. In fact, not only is the need for the delicate procedure to generate radially polarised beams overcome, but also the relative alignment between the linearly polarised beam and the tip modification is no longer critical

Ultimate Strength of Building Structures against Earthquake

我國の都市建築物は震度O.1,材料安全率3を用ひて設計されて居るが,從来の大地震に於ては震度0.2以上にも達し,而も構造物振動が地震と共鳴する時は構造各部の振動は地動に比して著しく大となる.依て地動,構造物の彈性振動,内部抵抗等を考慮し,n囘の半振動間共鳴の後に於て構造が實際に耐え得る極限の震度を四階及九階の建物の實例に就て計算したものであるが,其の結果m=3,n=6の場合に於て,四階建はO.2位の震度に耐え而も耐震力は上方に増大するが(第6圖),九階建にありてはO.18位で高さの中央部が割合に弱く,叉桁と柱とに於ても耐え得る極限の震度が梢著しく異なり,從つて従来の静力的計算法が其根底に於て若干の變更を要することを認める

Seismic Earth Pressures on Deep Stiff Walls

Experimental and numerical studies of the seismic response of a deep, stiff basement structure were motivated by the fact that the current seismic design methodologies based on previous works predict very large dynamic forces in areas of high seismicity. The experimental program consisted of a geotechnical centrifuge model with a basement structure embedded in cohesionless backfill. The numerical analyses sought to replicate the results of the centrifuge experiment and to validate the use of numerical analyses for the prediction of expected behavior. Overall, the results of this study show that the Mononobe-Okabe method of analysis provides a reasonable estimate of the expected response of stiff basement structures provided depth-Averaged design accelerations are considered