Even if the houses are built based on the same seismic resistance standards, some are damaged or not, and some may or may not collapse during an earthquake. This difference is considered to be due to the difference in local seismic motion or the target design level, the certainty of construction, the degree of deterioration, and the like. Besides, in wooden constructions, the strength and rigidity of the materials used, the joints, and the shear walls are not constant, so-called variations, which causes a difference in the load-deformation relationship of the layers. It is thought that the above factors cause differences in the response deformation during earthquakes. In this study, we discuss variations in response deformation caused by variations in materials, with the same input seismic motion, building design level, and load capacity.
Five or three full-scale box-shaped test specimens manufactured under the same conditions were simultaneously vibrated on the same shake table, and the variation in response displacement was quantitatively clarified. Also, the differences in the metal joints at the ends of the braces and the effects of finishing materials and orthogonal walls on the yield strength were examined. The experiments performed for three different purposes are the A-, B- and C-series shown below (Table 1). The A-series is to examine the variation of the response by simultaneously vibrating 5 test pieces with the uniform wall magnification and construction method on the same shaking table (Fig.1-2, Table2-3). The B-series examines the effect of hardware on the displacement response, using the hardware at the end of the brace with the same wall magnification as a parameter (Fig.8, Table9-10). Finally, the C-series examines the effect of differences in the plane type of hanging walls and frames on the displacement response, as well as the wall magnification (Fig.16-17, Table16-17).
As for the shear walls specimens in the A-series, the variation in response displacement up to the maximum load was small, about 7%, but where the maximum load is exceeded or not exceeded, the variation in response displacement was about 28%. For the brace specimens in the B series, the variation in response displacement increased when buckling in the brace and damage at its ends occurred. It is considered that this is influenced by the material strength and the performance of the brace end hardware. These tendencies were suggested in the C-series to be similar with or without lintel or orthogonal walls.
