SEISAN KENKYU
Online ISSN : 1881-2058
Print ISSN : 0037-105X
ISSN-L : 0037-105X
Volume 60 , Issue 2
Showing 1-15 articles out of 15 articles from the selected issue
(ERS)
Introduction to Special Section
Research Flash
  • Takashi KIYOTA, Takeshi SATO, Junichi KOSEKI
    2008 Volume 60 Issue 2 Pages 103-106
    Published: 2008
    Released: April 08, 2008
    JOURNAL FREE ACCESS
       Extremely large deformation of liquefied ground has been observed in several case histories, such as the 1964 Niigata, 1983 Nihonkai-Chubu and 1995 Hyogoken-Nanbu earthquakes in Japan. In order to study such large deformation behavior, a medium-size hollow cylindrical apparatus that can shear the specimen up to double amplitude shear strain of about 100% has been developed. With this apparatus, a series of undrained cyclic torsional shear tests was performed on saturated Toyoura sand. As a result, the limiting value of overall shear strain to initiate strain localization was found to increase with a decrease in the relative density of the specimen. [This abstract is not included in the PDF]
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  • Hiroshi KAMEYA, Jianliang DENG, Yukika TSUTSUMI, Junichi KOSEKI
    2008 Volume 60 Issue 2 Pages 107-110
    Published: 2008
    Released: April 08, 2008
    JOURNAL FREE ACCESS
       The 2004 Niigata-ken Chuetsu earthquake caused a slope failure in Yokowatashi-area of Ojiya city, where a thin weathered tuffaceous sandstone layer was found as the slip surface. The authors investigated this slope failure by site-investigation, laboratory test of undisturbed samples and numerical analyses. The stability analysis revealed that this slope would not be ruptured by the ground water level change due to rainfall without any earthquake load, but the slope stability during the earthquake should have been influenced by the preceding heavy rainfall. In addition, it is inferred that the alternating loading by the earthquake played a significant role for the failure occurrence. [This abstract is not included in the PDF]
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  • Iuko TSUWA, Kei KATO, HyeWon KIM, Mikio KOSHIHARA
    2008 Volume 60 Issue 2 Pages 111-114
    Published: 2008
    Released: April 08, 2008
    JOURNAL FREE ACCESS
       In order to clarify the vibration characteristics of a traditional timber frame including KUMIMONO, which is one of the components in traditional wooden structures, we performed the vibration test of one frame in a traditional timber structure.
    The Load-Deformation Relationship included the Restoring-Force Characteristics of Column. The shape swelled after the column deformation angle of about 1/20 rad. The deformation of KUMIMONO was infinitesimal compared with one of the whole frame. Therefore, in such frame case, KUMIMONO is thought as a rigid body. From the result of a model considering only the spring of columns, two things were clarified. One is that the hysteretic curve back to 0 corresponds to the force of one column. The other is that the modeling other elements are needed. [This abstract is not included in the PDF]
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  • Masahiro MATSUDA, Kei KATO, Mikio KOSHIHARA
    2008 Volume 60 Issue 2 Pages 115-118
    Published: 2008
    Released: April 08, 2008
    JOURNAL FREE ACCESS
       This paper presents the results of shaking table test of structural timber flame with hanging wall of traditional timber houses. The aim of this research is to understand dynamic and ultimate behavior of structural timber flame with hanging wall.
       As a result of the test, it was clarified that there is the case that pulling out the head jamb from the column causes reducing the bearing force of the structural timber flame and therefore the performance of joints between the column and the head jamb beam is important. [This abstract is not included in the PDF]
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  • Yuuki FUKUMOTO, Mikio KOSHIHARA
    2008 Volume 60 Issue 2 Pages 119-123
    Published: 2008
    Released: April 08, 2008
    JOURNAL FREE ACCESS
       Microtremor Observation is popularly practiced as a nondestructive-seismic-test for existing wooden houses, however we have to be aware that vibration characteristics in microtremor lever is not the same as the one under huge earthquake with a nonlinear characteristics of load-deformation-curve(P-δ).
    In this paper, we performed destructive shaking table tests and multiple microtremor tests and demonstrate the relationship of both secant stiffness. Also we examined the availability of microtremor as a relative index. [This abstract is not included in the PDF]
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Research Review
Research Flash
  • Kawin WORAKANCHANA, Paola MAYORCA, Ramesh GURAGAIN, Sathiparan NAVARAT ...
    2008 Volume 60 Issue 2 Pages 128-131
    Published: 2008
    Released: April 08, 2008
    JOURNAL FREE ACCESS
       Masonry, through its long history, is widespread used around the world and still remains a main building material in many places especially developing countries. However a poorly designed masonry is known as brittle and susceptible to the earthquake. To improve their seismic capacity, polypropylene band retrofitting technique method was purposed base on economic point of view and local availability of material and skilled labor. In this study, we proposed 3-D Applied Element Method as an analysis tool to help understanding the polypropylene band retrofitted masonry behavior which will be benefit in the future design process. Unlike the previous version, 3-D Applied Element Method elements can be any rectangular prism which help reducing the number of elements. Brick and mortar springs are represented by using different spring properties. Nonlinear constitutive law of the mortar spring employed the Gambarotta model which considers the material softening. Polypropylene band is modeled as beam element using conventional plastic constitutive law connected together with the masonry by elastic spring representing the polypropylene band to brick connector. The numerical simulation of non-retrofitted and retrofitted out of plane wallets shows that with the suitable selected parameter the behavior of masonry can be closely reproduced. [This abstract is not included in the PDF]
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Field Report
Research Flash
  • Ryo SHIRAKASHI, Kiyoshi TAKANO, Christophe PROVIN, Yasuyuki SAKAI, Ter ...
    2008 Volume 60 Issue 2 Pages 143-146
    Published: 2008
    Released: April 08, 2008
    JOURNAL FREE ACCESS
       Engineered tissues, in which digestion and/or metabolism play main role, require the high number density of cells (~107-108cells/mL) to perform its as high physiological functions as in vivo. A method of production and designing such an engineered tissue in vitro is a basic technology in the tissue engineering field. This study proposed universal method of high-density cell culture, including designing of scaffold shape and medium flow rate. That is, a plate type scaffold with microstructures was designed to allow 107-108cells/mL HepG2 cells adhering on the scaffold. Optimum flow rate of medium, which supplies enough nutrition (glucose) and oxygen to support this high cell density, and the microstructure were calculated by biotransport analysis accounting the detachment and starvation of cells. [This abstract is not included in the PDF]
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Research Review
Research Flash
  • Shigefumi TOKUDA, Takeshi UNEMURA, Marie OSHIMA
    2008 Volume 60 Issue 2 Pages 164-167
    Published: 2008
    Released: April 08, 2008
    JOURNAL FREE ACCESS
       Atherosclerosis is one of the causes of cardiovascular diseases or celebrovascular disorders. Low density lipoprotein transport through an arterial wall and accumulation is considered as a main factor in the early stage of initiation of atherosclerosis. On the other hand, it is known that mechanical forces such as wall shear stress (WSS ) influence the uptake function of endothelial cells and the preferential site of atherosclerosis is associated with low WSS region.
       In this paper, to investigate the effects of WSS on mass transport, the blood flow and solute transport in the lumen and arterial wall are modeled taking account of the multi-layered structure of arterial wall. A shear-dependent hydraulic conductivity and permeability is employed. As a result, solute concentration in arterial wall increases in the areas where WSS is low. It shows that low WSS affects solute accumulation in the arterial wall and initiation of atherosclerosis. [This abstract is not included in the PDF]
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