To analyze why a lot of buildings collapsed in Mashiki town by the 2016 Kumamoto earthquake, we compared the distribution of collapsed buildings with the construction years and the result of microtremor measurements of the ground. The collapsed buildings and the construction years were judged from some aerial photographs. This study reveals that the damaged area shapes like a band, and the band caused by the foreshock is different from the band caused by the main shock. The severest area includes many collapsed wooden buildings built after Order for Enforcement of the Building Standard Act amended in 1981. In the same area, the ratios of the collapsed buildings built before 1982 and after 1982 are almost same.

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The objective of this study is to suggest a new type of reinforcing elements, Amida-shaped frame, for traditional wooden structures. First, to make clear the mechanical characteristics of Amida-shaped frames, we conduct the static loading tests of them. Next, we analyze the difference of the restoring force characteristics and the damages between frames in parameters, size and the number of horizontal members. Finally, we simulate the static loading tests with analysis models to confirm the mechanical characteristics which can't be identified at the experiments.

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In this paper, we report the results of static loading tests on traditional wooden two-storied frames with through columns. The tests target a frame with column reinforced with a stainless steel plate and a frame reinforced with an FMS alloy damper for the purpose of reinforcing the joints against fracture caused by the axial force and bending moment of beams "Sashigamoi". We also propose a practical 2-dimensional FEM model that evaluates the behavior of the joint and the frame of the traditional wooden two-storied frames, and compare the analysis results with the experimental results.