Preliminary study on detection of wood structure defects and evaluation of residual elastic modulus

In order to make a non-destructive evaluation of defects in wood structures of ancient architecture and the residual modulus of elasticity，this study measured on-site wood structures from the main hall of the Baoguo Temple, Zhejiang Province, using a three-dimensional stress wave method．Results show that this three-dimensional stress wave is an effective method to detect on-site the defects in wood structure of ancient architecture，not only at the same height，but also at various heights of the columns. Based on the variation of velocity of longitudinal stress wave between sections，defects were mainly found in the near-ground region. The residual modulus of elasticity was also quite successfully evaluated by the three-dimensional stress wave method in wood structure of ancient architecture. Distance between sensors had little effect on the average longitudinal residual modulus of elasticity.