EFFECT OF THICKNESS AND SPAN IN BENDING DEFORMATION OF WOOD PANELS

ABSTRACT

This study aimed to evaluate the correlation between the physical and mechanical properties of MDF (Medium Density Fiberboard) and MDP (Medium Density Particleboard) used in furniture manufacturing. The physical properties density and moisture content and the mechanical properties static bending (MOE and MOR) were determined. The experiment was made with three panel thicknesses (15 mm, 18 mm and 25 mm) and three different spans with relationship L/h (span divided by thickness) of 30, 35 and 40 totaling nine treatments for each type of panel with three replications. These samples were subjected to nondestructive bending test, with loads equivalent to 25 g.cm^-² uniformly distributed in conditioned environment (temperature 20º C ±1, humidity 65% ±1). The final deformation load was recorded after a week, and the residual deformation, after removal of the load, was also registered. Statistical analysis of the results evaluated the effect of treatments relative to the span and thickness. The analysis showed significant differences between the results for each thickness, however, the span demonstrated greater influence than the thickness. Among the sample sizes evaluated the best value found was L/h = 30.

Keywords:
Deflection; Mechanical testing; Dimensioning of parts