Bending Strength Evaluation of Japanese Wooden Cultural Heritage Building Columns Based on a Non-Destructive Testing Method

ABSTRACT

Column failure assessment is essential for seismic diagnosis of Japanese wooden cultural heritage buildings. Achieving accurate column failure assessment depends on accurately estimating the bending Young’s modulus (E_b) and characteristic bending strength (F_b) of columns. This study extends the application of a non-destructive testing (NDT) method to estimate E_b and F_b of Japanese cedar columns generally used in wooden cultural heritage buildings. For this purpose, a correlation between the dynamic bending Young’s modulus (E_p) and E_b of Japanese cedar columns is established and the variations in the E_p–E_b relationship across different wood provenances and species are clarified. Using the proposed method, a statistical analysis of the estimated E_b of Japanese wooden cultural heritage buildings is provided. Furthermore, estimated E_b is used to determine F_b of the columns using the mechanical grade classification system. The results show that most Japanese cypress and Japanese cedar columns feature higher F_b than those used in conventional seismic diagnosis. Conversely, two-thirds of the Japanese red pine columns feature a lower F_b than that used in conventional seismic diagnosis. The proposed F_b evaluation method offers an NDT method that can be widely applied to Japanese wooden cultural heritage buildings to assess column failure more accurately.

KEYWORDS:

• Bending strength
• bending Young’s modulus
• column
• cultural heritage
• impact elastic wave test
• non-destructive test
• seismic diagnosis
• traditional wooden building

Acknowledgments

The authors thank Yasuhiro Hayashi (President, National Institute of Technology, Maizuru College) for the assistance with this research. Part of this article was submitted as an abstract (Fu et al. 2021a; S. Iijima et al. 2021) at the annual meeting of the Architectural Institute of Japan.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was supported by JSPS under Grants-in-Aid for Scientific Research [JP19H00793] and in part by JST SPRING under Grant [JPMJSP2110].