Research concerning the seismic damage decrease of the traditional wooden building and the cultural asset enshrined there.

对传统木结构建筑及其文化遗产的抗震减损进行了研究。实验建筑是长野县宫田镇的三层木塔和长野市的正源寺主庙。在文物减震方面，回顾了以往有关隔震器的研究成果。结合三层塔的修复工作，研究了三层塔修复前后的振动特性。微震持续了约30分钟。根据微颤的第一阶固有频率，进行了人体力量激发的共振实验。因此，修复前和修复后的固有频率分别为1.5Hz、2.3Hz、3.7Hz。阻尼常数约为0.03。得到了三阶振型的振动模态。第一模态为弯曲变形，第二模态为剪切变形。振动测量是在修复长野市正源寺大殿之前进行的。至于修理后的测量，计划在修理完成后进行。观察了30分钟的微震，以及真易寺三层塔的情况。并进行了与第一固有频率相匹配的人的力量激励的共振实验。因此，修复前的第一固有频率为1.35Hz，修复后的第一固有频率为1.45Hz。阻尼常数分别为0.026和0.027。在文物减震方面，回顾了以往有关隔震器的研究成果。据了解，在JMA神户NS修正地震波作用下，地震响应加速度降低约1/12，最大速度调整为50 kine。

We researched concerning the seismic damage decrease of the traditional wooden building and the cultural asset enshrined there. Experimented buildings are the three-storied wooden pagoda in Miyota town in Nagano Prefecture and the main temple of Shogenji in Nagano City. About the seismic damage decrease of the cultural asset, study results concerning the seismic isolator in the past were examined. The vibration characteristic before it repaired and after it had repaired was examined along with the repair of the three-storied pagoda. The microtremor was observed for about 30 minutes. Moreover, the resonance experiment by the human strength excitation was done according to the first natural frequency that had been obtained from the microtremor. As a result, natural frequency was 1.5Hz, 2.3Hz, 3.7Hz before it repaired and after it had repaired respectively. The damping constant was about 0.03. The mode of vibrations were obtained up to third modes. The first mode showed bending deformation, and the second mode showed shearing deformation. The vibration measurement was done while repairing before it repaired along with the repair of the main temple of Shogenji that existed in Nagano City. As for the measurement after it repairs, it is scheduled to do after the repair is completed. The microtremor was observed for 30 minutes as well as the case of true easy temple Three-Storied Pagoda. And, the resonance experiment by the human strength excitation matched to the first natural frequency was conducted. As a result, the first natural frequency was 1.35Hz before it repaired and was 1.45Hz under the repair. The damping constant were 0.026 and 0.027 respectively. About the seismic damage decrease of the cultural asset, study results concerning the seismic isolator in the past were examined. It has been understood that response acceleration decrease about 1/12 against the revised earthquake wave of JMA Kobe NS, adjusting to 50 kine as the maximum velocity value.