Effect of forming stresses on the strength of curved laminated beams of loblolly pine

Abstract

Curvature-stress factors reflecting the effect of forming stresses in producing curved beams of thin vertical-grain laminations of clear wood have been determined for loblolly pine. Strength retention of curved beams decreases with increasing severity of curvature but not to the degree suggested by the Wilson equation commonly used in design. Curved beams loaded on the convex face (stresses reverses) are stronger than beams loaded on the concave face (stresses additive) and curvature-stress factors applicable to these two conditions are recommended. wood quality characteristics favoring higher retention of curved beam strength are suggested.

Citation

Woodson, George E.; Wangaard, Frederick F. 1969. Effect of forming stresses on the strength of curved laminated beams of loblolly pine. Forest Products Journal, Vol. 19(3): 47-58