• Altiero, Kris A.
  University of Maine
  

This investigation was initiated to examine both the immediate and perm.anent effects of low temperature exposure on certain mechanical properties of structural flakeboard, conditioned to low and high moisture contents. The material evaluated was a commercially  manufactured, 7/16- inch,  aspen-based  oriented  strandboard.Test specimens were prepared from five full-sized (4-foot x 8-foot) panels  of  oriented  strandboard.  The  samples  were  then   randomly selected  for exposure  at one of three  moisture  conditions:   (a)   ambient (5-7 percent moisture content), (b) 12-hour watersoak and  (c)  24-hour watersoak. After moisture treatment, specimens  from  each  moisture condition were exposed  to  one  of  three  temperature  conditions:  (a) ambient  temperature  (68-70°F),  (b)  freezing  and  (c)   freezing-thawing. The freezing treatment consisted of 24 hours of 0°F. The freeze-thaw condition included 24 hours at 0°F followed by 24  hours  at  room temperature (68-72°F). Mechanical property determination was conducted immediately following the prescribed temperature conditioning. All mechanical properties were evaluated  in  both  the  long  and   cross-panel directions in order to determine the effect of flake alignment. The mechanical properties evaluated included modulus of rupture (MOR), modulus of elasticity (MOE), and compression-shear strength; MOR and MOE were determined using a static bending test, and compression-shear strength was determined from the Minnesota Shear Test  apparatus.