Most traditional disaster information systems are necessary to post expert staff with high computer literacy to operate the system quickly and correctly in the tense situation when a disaster occurs. However, in the current disaster response system of local governments, it is not easy for local governments to post such expert staff because they are struggling with staff cuts due to administrative and fiscal reform. In this research, we propose a disaster information management system that can be easily operated, even under the disorderly conditions of a disaster, by municipal personnel in charge of disaster management. This system achieves usability enabling easy input of damage information, even by local government staff with no expertise, by using a digital pen and tabletop user interface. Evaluation was conducted by prospective users using a prototype, and the evaluation results are satisfactory with regard to the function and operationality of the proposed system.

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A modified method of the 2^nd level screening procedure to prevent story collapse of middle-high rise steel reinforced concrete structure at digit direction is proposed. The result of seismic response analysis shows that column-overdesign-factor and seismic performance distribution of the height direction affect on a potential of the concentration of damage to the specific layer. Therefore, the criteria of the column-overdesign-factor and seismic performance distribution of the height direction to avoid the intermediate damage at the specific layer is indicated.

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We derived a relationship between source, site amplification spectrum and amplification factor, a formula to evaluate an amplification factor is proposed based on the relationship. In this study, we improve the formula by revising site amplification spectrum. A relationship between amplification factors calculated by the formula and moment magnitude Mw are examined, it found that amplification factors for PGV vary greatly according to Mw. The calculated amplification factors are compared with the observed value evaluated by multiple reflection theory. As a result, if site amplification spectrum is fit for theoretical spectrum, the calculated amplification factors for PGV are in good agreement with observed value.

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During the 2011 off the Pacific coast of Tohoku Earthquake, Rokko Bridge, Ibaraki Prefecture, Japan, suffered significant damage including loss of two piers and three spans. In this study, to evaluate ground motions at the damage site, temporary aftershock observation was conducted at the site. The evaluated site amplification and phase effects between the damage site and JMA Hokota site are very similar. It indicates that the observed ground motions at JMA Hokota site during the 2011 main shock can be regarded as the ground motion at the damage site.

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