This paper presents seismic capacity of low-medium-rise building which obtained by seismic rehabilitation by means of hysteretic dampers when subjected to variant strong ground motions. Peak velocity of input earthquake motion (Vo) inducing ulitimate limit deformation of building is utilized as a index evaluating its seismic capacity. Conclusions are summarized as follows.
(1) Vo increses in propotion to the amount of equipping hysteretic dampers. but Amplitude of Vo vary with the characteristics of input earthquake motions.
(2) Statistical values of Vo are evaluated by the response using simulated earthquake motion which consider the variation of response spectrum and wave form. The coefficient of variation (COV) for Vo of the model with hysteretic dampers is approximately 0.20.
Vo from μ-σtoμ+σ(μ: mean, σ: standard deviation) is evaluated by the response using simulated waves which adopt the response spectrum from attenuation equation.
(3) Vo distribution considered its statistical values is compared with earthquake ground motion levels in accordance with mean return periods (Tr). Seismic rehabilitation is effective in Tr=73, 475year. Bacause of a probability of exceeding its ulitimate limit state is reduced in relatively large amount.

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This study sets out a methodology for estimating a city's potential seismic risk. This methodology, which considers all phases of an earthquake disaster, is based on regional characteristics that are derived from macro-information such as topography, climate, location of active faults, regional building types and their seismic capacity, experience of past earthquake disasters, inter-city traffic systems, and accessibility from neighboring cities, as well as from the micro-information presently used in current methodologies such as soil and building conditions, open areas, fire-resistant buildings, and building-to-land ratios. This methodology was applied to typical cities in Japan. The degree to which this methodology was able to accurately assess the potential seismic risk and earthquake disaster patterns for these cities are also discussed herein.

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Damage statistics for the 1923 Kanto earthquake frequently show some inconsistency in amount of damages. Some datasets provide different numbers of damages from another for the same municipality. It has turned out that these differences are caused by; 1) the difference in measure of damages using number of buildings or number of households, 2) the number of non-residential buildings that were occasionally summed up in datasets, and 3) whether buildings burnt down after collapse by shaking were taken into account or not. A newly developed dataset is presented in this paper for specifying uniform numbers of damaged houses due to the Kanto earthquake, in which the damage data have been re-evaluated from the report by Matsuzawa (1925) and Ministry of Home Affairs (1926). A seismic intensity distribution estimated from the collapse rate of houses is also shown covering the entire region of the affected area. It is confirmed that the relationship between the seismic intensity and the ground condition can be clarified precisely from the new dataset.

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