EFFECT OF ENVIRONMENTAL CONDITIONS ON THE MECHANICAL BEHAVIOR OF WOOD COMPOSITE I-BEAMS (I-BEAMS).
Contributors: Auburn University.
Published: 1988
Number of pages: 233
Subjects: Agriculture, Wood Technology.; Applied Mechanics.; Health Sciences, Nursing.
Description: This study was undertaken to investigate the effect of humidity on the engineering performance of wood composite I-beams. The I-beam component material properties as affected by the humidity level were first evaluated to determine the material constants needed for the theoretical analysis.

Short-term static bending tests were then performed to determine the strength, failure modes, and the load-deflection characteristics of the full-size I-beams under different environmental conditions and the results were compared with those of southern pine lumber 2 x 10s. Fundamental composite beam theory was employed to check the experimental results.

Creep behavior of the full-size composite I-beams and structural lumber members under changing humidity was then evaluated under two testing conditions: dry-humid-dry and humid-dry-humid cyclic exposures. A four-element creep model was used to approximate the experimental data by using a nonlinear least square procedure. An improved model combining the creep-induced and the moisture-induced strains was developed for the prediction of creep behavior of I-beams and lumber members under changing humidity.

The finite element method was used to theoretically analyze the stress distributions as well as the displacements in I-beams loaded under different humidity levels. Good agreement between experimental data and predicted values was observed for each beam type.
Notes: Source: Dissertation Abstracts International, Volume: 50-08, Section: B, page: 3248.

Thesis (PH.D.)--AUBURN UNIVERSITY, 1988.

School code: 0012.