Design of Wood Members Under Combined Load

A new design criterion for wood members under combined axial and bending loads is proposed. The new equation covers biaxial bending, axial load, and water ponding. It employs Ylinen's column formula for beam or column buckling, and replaces the linear interaction equation with more accurate equations based on recent test data and results of elastic stability analysis. Despite its simplicity, the proposed criterion is more general, more rational and more accurate than the existing design criterion.