Fracture Analysis of Wood in Moment-Resisting Joints with Four Drift-Pins Using Digital Image Correlation Method(DIC)
Seiichiro UKYO and Minoru MASUDA
Abstract:The deformation behaviour of wood around moment-resisting joints was analysed using digital image correlation methodiDICjand finite element method iFEMj. The joints were consisted of four drift-pins. The distribution of the strain perpendicular to grain and the shear strain parallel to the grain were examined around each drift-pin to evaluate the large deformed area and the location of initial failure. Results were as follows. Areas of large compression strain perpendicular to the grain and large shear strain were observed in the predicted loading area of each drift-pin. Large tensile strain perpendicular to the grain was observed at the area close to the loading ( contacting ) area of the drift-pins, and the tension area was partly overlapped with the area of large shear strain.The overlapped area coincided with the location of initial cracks propagated parallel to the grain.This coincidence suggested that the cracks occurred by mixed-mode fracture in this joints. The numerical results by finite element analysis were compared with the experimental results obtained with DIC and they gave good agreement with each other. Key Words:Moment-Resisting joints,Digital Image Correlation,Strain distribution,Initial crack,Mixed mode fracture