Since wooden tanks are used as a water receiving tank in important installations, such as a public facility and a hospital, the functional maintenance in case of a big earthquake is indispensable performance. However, study of the anti-earthquake design in wooden tanks is not progressing. In this study, the displacement response, acceleration response, and distorted response of wooden tanks were analyzed from the vibration experiments by the level earthquake motion exceeding 1G. And to the level earthquake motion in which the main structural members of the wooden tanks used in this experiment exceed 1G, the destruction which spoils a function was considered not to be generated and obtained the underlying data for the safety check in case of an earthquake from the experimental result about the action at the time of strong vibration.

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This paper aims at making clear that who is most vulnerable in disaster as the attack by an inland or oceanic earthquake. The motivation is simply to ascertain whether it is true or not that the infants and the elderly people have long been situated as the extremely vulnerable age groups in disaster. In this purpose we made a special effort to get a comprehensive consideration of mortality changes by age groups from infants to elderly in acute period of the attack by the earthquake, paying special effort to expand our retrieval of articles over traditional seismological journals to medical journals while consulting well-prepared ones as PubMed Data Base. Thus, totally 10 earthquakes of 5 domestic and 5 overseas are retrieved. What we found are that there are 2 major patterns of U and J types as is represented in English bold letter, in case when we introduce 2 dimensional coordinate having X axis as increasing age groups and Y axis as age-specific mortality, and also that there are two additional patterns of age-independent; one is the initial case with the lowest mortality near to zero, and the other the case with extremely high mortality and therefore the latter two cases can't be age-dependent. We also paid attention to understand why we see such various patterns in terms of age-dependency. Considered are factors as the strength of earthquake shaking (tsunami height), age-reflecting behavioral performance and further factors on whether earthquake protection schemes in both of hard- and soft-wares are prepared or not, together with occurrence time, date, season and so on. Finally we made a special effort to figure out the severity of mortality in view of how such response patterns transfer from one to another. Our findings as above are significant for exploring better protection and mitigation schemes against human victims due to inland and oceanic earthquakes.

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This paper summarizes liquefaction-induced damage in the Kanto region during the M_w9.0 Off the Pacific Coast of Tohoku earthquake of March 11, 2011, focusing on land and geomorphologic conditions of affected areas. Based on this study the following conclusions were reached: liquefaction was observed at a total of 130 cities, towns and villages in all seven prefectures in Kanto regions, whose numbers of 7.5-arc-second grid cells are 7,987; most of the liquefaction occurred in the areas where the instrumental seismic intensity exceeded 5.0; liquefaction took placed in the areas along the big rivers and filled land along the Tokyo Bay and developed land in the small valleys among the terrace; and liquefaction occurrence rate for each geomorphologic unit within the areas of the instrumental seismic intensity exceeded 5.0 is the highest for filled land (25.7%) among 23 geomorphologic unit.

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A macroscopic model, macro plate model, was proposed to represent a wall member of RC walls. Both in-plane and out-of-plane behavior were considered for numerical derivations of macro plate model. For out-of-plane behavior, bending deformation was incorporated with shear deformation to consider out-of-plane deformation as same as in-plane behavior. The hysteretic behavior of macro plate model can be directly expressed by stress-strain relationships in any conventional hysteretic rules, which have been proposed by other researchers, for member level. Unless nonlinear analysis of RC walls was proposed in case of earthquake, macro plate model can be proposed for nonlinear analysis of those in case of wind and tsunami by converting distributed force to nodal force.

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In the previous study, the author proposed empirical equations to predict uniform durations of specified levels of JMA seismic intensity under given values of predicted or observed JMA seismic intensity. On this basis, this study presents a consistent scheme for empirical prediction of JMA seismic intensity and its duration by combining a GMPE and conditional prediction equations for duration of eight kinds of threshold intensity. Prediction equations for uniform duration of specified intensity levels have been probabilistically derived incorporating considering uncertainty of predicted JMA seismic intensity. As a demonstration of the proposed scheme, seismic intensity maps are shown together with duration maps for a scenario earthquake.

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For the purpose of the ground motion estimation at a very near site from a fault, we prepared the theoretical simulation method based on the Green's function formula for uniform elastic fullspace, and evaluated integral error of the simulated theoretical ground motion at a very near site from a fault. As a result, the element size for integral had to be less than half of the distance between the element and the site. And, the effective element division was suggested for the fault which outcroped to the ground surface. Furthermore, the theoretical motion was simulated numerically at a very near site from a fault, in the case that the strong ground motion generated from the surface area, which lay from the seismogenic upper limit to the surface. Under consideration for ground motion generation from the surface area, it was illustrated that the predicted maximum velocity (in average) and maximum acceleration (in average) were about 1.5 times for without consideration of the surface area when hypocenter located the bottom right of the SMGA.

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A method for estimating the average shear-wave velocity to 30m (V_S30) from a shallow velocity profile is examined by using data from 2,099 boreholes in Japan. Correlations between V_S30 and shallower average velocity show dependence of the shear-wave velocity at the deepest layer of the shallow profile, and empirical equations to estimate V_S30 are proposed as a function of shallower average velocity and velocity at the deepest layer.

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In the Tohoku earthquake, reclaimed lands as well as residential houses build on such a land were severely damaged. The present study investigates causes of those damages by classifying the properties of the input motion, ground conditions, and construction ages. As a result, compared with the damage rate of the houses located on a land constructed by cutting hills, those on filled valley and their boundary show much higher, more than double, damage rate.

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[in Japanese]

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