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

Abstract

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.