Forces acting on bridge abutments over liquefied ground     

Akihiro Takahashi  Hideki Sugita  Shunsuke Tanimoto 《Soil Dynamics and Earthquake Engineering》2010

Large earthquake-induced displacements of a bridge abutment can occur, when the bridge is built on a floodplain or reclaimed area, i.e., liquefiable ground, and crosses a water channel. Seismic responses of a bridge abutment on liquefiable ground are the consequence of complex interactions between the abutment and surrounding soils. Therefore identification of the factors dominating the abutment response is important for the development of simplified seismic design methods. This paper presents the results of dynamic three-dimensional finite element analyses of bridge abutments adjacent to a river dike, including the effect of liquefaction of the underlying ground using earthquake motions widely used in Japan. The analysis shows that conventional design methods may underestimate the permanent abutment displacements unless the following two items are considered: (1) softening of the soil beneath the liquefiable layer, due to cyclic shearing of the soil surrounding the piles, and (2) the forces acting on the side faces of the abutment.  相似文献   

Intercomparisons of Experimental Convective Heat Transfer Coefficients and Mass Transfer Coefficients of Urban Surfaces     

Aya?HagishimaEmail author  Jun?Tanimoto  Ken-ich?Narita 《Boundary-Layer Meteorology》2005,117(3):551-576

The convective heat transfer coefficient (CHTC) of an urban canopy is a crucial parameter for estimating the turbulent heat flux in an urban area. We compared recent experimental research on the CHTC and the mass transfer coefficient (MTC) of urban surfaces in the field and in wind tunnels. Our findings are summarised as follows.

(1)	In full-scale measurements on horizontal building roofs, the CHTC is sensitive to the height of the reference wind speed for heights below 1.5 m but is relatively independent of roof size.
(2)	In full-scale measurements of vertical building walls, the dependence of the CHTC on wind speed is significantly influenced by the choice of the measurement position and wall size. The CHTC of the edge of the building wall is much higher than that near the centre.
(3)	In spite of differences of the measurement methods, wind-tunnel experiments of the MTC give similar relations between the ratio of street width to canopy height in the urban canopy. Moreover, this relationship is consistent with known properties of the flow regime of an urban canopy.
(4)	Full-scale measurements on roofs result in a non-dimensional CHTC several tens of times greater than that in scale-model experiments with the same Reynolds number.

Although there is some agreement in the measured values, our overall understanding of the CHTC remains too low for accurate modelling of urban climate.  相似文献   

Rapid tectonics of the Late Miocene Boso accretionary prism related to the Izu–Bonin arc collision     

Yuzuru  Yamamoto  Shunsuke  Kawakami 《Island Arc》2005,14(2):178-198

Abstract   The structure, paleomagnetism and biostratigraphy of the Nishizaki and Kagamigaura formations on the southern Boso Peninsula, central Japan, were investigated to determine the chronographic constraints on the accretion, post-Late Miocene rotation and regional tectonics in the Izu–Bonin island arc collision zone. The geological structures on the southern Boso Peninsula are characterized by an east–west trending and south-verging fold and thrust belt that curves toward the northwest–southeast in the northwest extent of the Nishizaki Formation. Two stages of tectonic rotation were revealed by paleomagnetic and structural studies. The first is believed to have occurred after the accretion of the Nishizaki Formation and before the deposition of the Kagamigaura Formation, while the second is confidently correlated with the 1 Ma Izu block collision. The northwest extent of the Nishizaki Formation was rotated clockwise by approximately 65–80°, whereas the rotation was only 25–30° in the east, and 11–13° in the overlying Kagamigaura Formation. Radiolarian biostratigraphy suggests a depositional age of 9.9–6.8 Ma (Upper Miocene period) for the Nishizaki Formation and 4.19-3.75 Ma (Pliocene period) for the lower Kagamigaura Formation. These results indicate that the age of accretion and first-stage rotation of the Nishizaki Formation can be constrained to the interval of 6.80–3.75 Ma. This structure most likely represents the northward bending caused by collisions of the Tanzawa and Izu blocks with the Honshu island arc, and suggests rapid processes of accretion, collision, uplift and the formation of new sedimentary basins within a relatively short period of time (2.61–3.05 my).  相似文献   

Inversion of the HZ ratio of microseisms for S-wave velocity in the crust   总被引：1，自引：1，他引：1  

T. Tanimoto  C. Alvizuri 《Geophysical Journal International》2006,165(1):323-335

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Seasonality in particle motion of microseisms   总被引：5，自引：0，他引：5  

T. Tanimoto  S. Ishimaru  C. Alvizuri 《Geophysical Journal International》2006,166(1):253-266

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Teleseismic surface wave study for S-wave velocity structure under an array: Southern California   总被引：2，自引：0，他引：2  

K. Prindle  T. Tanimoto 《Geophysical Journal International》2006,166(2):601-621

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Comment on 'Metamorphic olivine after dehydration embrittlement in Serpentinite: Case study from the Shiraga Serpentinite mass in the Sanbagawa high P/T metamorphic belt,central Shikoku,Japan' by Fukumura,Okamoto and Terabayashi,https://doi.org/10.1111/iar.12293     

Simon R. Wallis  Shunsuke Endo 《Island Arc》2020,29(1)

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鲈鱼生长催乳素的分离纯化与N-末端序列分析   总被引：1，自引：1，他引：0  

徐斌  张培军  苗宏志  李德尚  森山俊介  川内浩司 《海洋学报》1998,20(2):83-89

生长催乳素(SL)是生长激素/催乳素家族的一种新的脑垂体蛋白质激素,本研究首次从鲈鱼脑垂体中分离得到.鲈鱼脑垂体在碱性条件下,经葡聚糖凝胶(SephadexG-100)过滤和反相高效液相色谱(rpHPLC)分离出纯化的鲈鱼生长催乳素,(sbSL),并与大麻哈鱼生长催乳素(sSL)抗体发生特异性的Western免疫印迹交叉反应证实.SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)分析,发现鲈鱼生长催乳素分别是由分子量为23.2×103和28.4×103u两种形式组成(后者可能是一种糖基化形式).根据Edman降解原理,测得鲈鱼生长催乳素的N-末端16个氨基酸的序列,它与已知鱼类生长催乳素的N-末端序列比较,具有较高的同源性;由此进一步证实,分离纯化得到的鲈鱼生长催乳素是正确的.  相似文献