Shear performance of southern pine glued orthogonally with phenol-resorcinol-formaldehyde or polyurethane

• Main Author: Cao, Guangmei
• Other Authors: Rubin Shmulsky
• Format: Others
• Language: en
• Published: MSSTATE 2018
• Subjects: Sustainable Bioproducts
• Online Access: http://sun.library.msstate.edu/ETD-db/theses/available/etd-03122018-113634/

<p>To provide fundamental information for the second generation of cross laminated timber manufacturing, wood sections that glued by different orientations were constructed and tested. To reveal adhesive differences, phenol resorcinol formaldehyde (PRF) and polyurethane (PU) adhesive were used and the gluelines were evaluated in accordance with different conditions for shear strength, wood failure, dimensional stability and delamination. A non-destructive testing method was applied to measure the dynamic modulus of elasticity (dMOE) change. The results showed that the radical wood section of lumber produced with the starsawn process had much less deformation and was more suitable for glueline. PRF had better performance than PU in terms of shear strength, dimensional stability, and delamination. Confocal microscopic pictures revealed that the tangential to tangential (TT) glueline showed the tendency of collapse, indicating a poor bond strength and therefore a poor glueline durability of TT glueline, especially when it was subject to wet conditions.</p>