Dynamic properties of traditional wooden temples located in Yurihonjo city, Japan

摘要

Old traditional wooden temples located in Yurihonjo city, Japan are investigated to determine their seismic characteristics and to evaluate their dynamic performance. These constructions are declared as buildings of cultural interest and therefore efforts are done to preserve this kind of buildings. Structure corresponds in general to framed wooden constructions with traditional connections between columns and beams. In general, nails are not used in these joints, and instead of them, the beam is narrowed at extreme to be inserted into a hole cut in the column. These buildings are supported by columns that rest directly on stone bases forming pinned joints. First, general evaluation to make a diagnosis of the structural condition was performed. Then, as an initial step to evaluate the seismic vulnerability of these historical buildings, dynamic characterization has been undertaken. For that purpose, measurements of the micro vibration of the building was planned and undertaken by the authors. Comparative study of the predominant periods of the structures is done by plotting the periods versus building heights. Preliminary results show that wooden temples in this region have long periods in comparison to temples of other regions of Japan. In addition, analytical finite element models were constructed to obtain the predominant period and shapes of vibration. These analytical results were compared with those obtained by means of ambient vibration.