END-NOTCHING EFFECT ON FLEXURAL STIFFNESS OF LUMBER - PRELIMINARY EVALUATION

Full-size beams of southern yellow pine and yellow-poplar were non-des tructively loaded in flatwise bending, and subsequently notched at the end and destructively loaded in edgewise bending. Flatwise beam stiff ness measured before notching was adjusted to its equivalent edgewise stiffness and compared with experimental results. Limited test results show that stiffness of end-notched wood beams was influenced by span- to-depth ratio, fractional notch depth, and notch location. The effect of end notching on beam stiffness of lumber has not been experimental ly addressed and previous theoretical analyses did not show a reductio n.