Analysis of information sources in references of the Wikipedia article "Shinbashira" in English language version.
The special ability of earthquake resistance of five-stories timber pagodas in Japan remain a mystery up to now. In this paper, a typical five-stories timber pagoda is considered in which its structural model includes friction bearings connecting the central pillar (shinbashira) and footing, the surrounding pillars and beams of roof. The unclarity in structural details and connections of the pagoda are characterized by various parameters such as the gap between the shinbashira and floors, the coefficient of friction and the weight of roof. The non-linear dynamic responses of the pagoda with the proposed model and the traditional model are then analysed together according to ground acceleration of various earthquake records. The obtained results indicate that the proposed model gives much lower response compared to that of the traditional model. This analysis helps clear understanding on the special earthquake resistance of Japanese pagodas that remained for centuries
The controversy [of the said pagoda being older than earlier thought] has arisen because a recent scientific examination of the shinbashira, the "heart post" that passes through the center of the pagoda, showed that the hinoki (Japanese cypress) wood used for this post was felled in A.D. 594. Assuming this timber was used shortly after it was felled, it means that the construction of the pagoda took place not at the beginning of the eighth century (around 711), as is generally believed, but about a century earlier. The generally held theory has it that Horyuji, including the pagoda, was first built around 607 by Prince Shotoku...quality of their construction is recognized by specialists throughout the world. In spite of the fact that the structure consists almost entirely of interlocking pieces of wood, the five-story pagoda has not succumbed to earthquakes, even though Japan is in a major earthquake zone.
