著者
八木 尚太朗 伊山 潤 福島 佳浩 吉敷 祥一 石田 孝徳 清家 剛 山田 哲
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.86, no.788, pp.1400-1411, 2021-10-30 (Released:2021-10-30)
参考文献数
19

From a viewpoint of continuous use of buildings after an earthquake, it is important to understand the behavior and damage progress of non-structural elements such as dry partition wall under a large deformation owing to earthquake, and to establish a method to monitor the condition of non-structural element in a qualitative manner as well as in a quantitative manner. In this paper, first the past studies on loading experiments for dry partition wall were summarized, showing that enough studies considering the effect of opening and the behavior of walls located away from beam location have not been done. Based on the review of past studies, a full-scale static loading test of steel moment frame with dry partition walls was performed. The specimen has two frames; one frame has a flat wall without opening and the other frame has a wall with a door opening and a corner in the frame. In the latter frame, some part of the wall is placed not directly under the beam. Static cyclic loading was applied, increasing the peak story drift up to as large as 1/33. In the experiment, visual observation was performed at each loading step. Rotation angle and vibration of the walls was also measured using MEMS acceleration sensors. The flat wall had relatively few board cracks and other damage. However, the boards on upper layer in the center part of the wall began to rock at the loading step of a 1/100 story drift. Then at 1/50, the boards showed out-of-plane deformation and when unloading after reaching 1/33, boards fell off. On the other hand, on the wall with the opening, a gap opening between the boards, and a crack on the L-shaped boards at the corner of the opening were observed at a relatively small story drift angle of 1/400. Regarding the wall located away from the beam, damage was concentrated on the wall which was orthogonal to the frame and not under the beam. The wall rotated around the vertical axis, and this was thought to be due to the difference of trackability to the structure between walls. Due to this behavior, a crack at the corner of the wall was seen at the story drift angle of 1/400, and at 1/75 the upper track opened, and studs were seen to come off. The rotation angle and the vibration of the walls were measured by MEMS acceleration sensors. The measurement result corresponded well with the damage observation. It was found from the measurement results that there were signs before damage and behavior of walls could be visually confirmed. Moreover, it was found that the vibration frequency of the damaged wall decreased (period became longer) as the loading progressed. This change may be representing the damage development in the wall. From these observations, it was confirmed that the MEMS acceleration sensor can capture small movement implying damage in partition wall in a quantitative manner, but more study should be necessary about the relationship between the measured deformation and the degree of damage and performance degradation, to utilize accelerometers for structural health monitoring of partition walls.
著者
秋山 宏 伊山 潤 原田 幸博
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.61, no.488, pp.49-55, 1996
参考文献数
7
被引用文献数
4 3

Hitherto, the overturning of rigid bodies under earthquakes have been dealt with in terms of the maximum ground accelaration and the maximum ground velocity. However, the adequate estimate for all shapes and sizes of rigid bodies has not been established yet. In this paper, the energy approach is applied to the overturning problem. By introducing the equivalent period of vibration, the energy inputs to rigid bodies are estimated based on the energy spectrum. The possibility of overturning is judged by equating the energy input to the potential energy of rigid bodies on the brim of overturning.