Virginia Tech
Investigating Differences in Douglas-fir and Southern Yellow Pine Bonding Properties
Abstract
dc:description.abstractDifferences in southern yellow pine (represented by Pinus taeda) and Douglas-fir (Pseudotsuga menziesii) mature and juvenile wood were examined in terms of density, chemical composition, surface energy, shear stress, % wood failure, and delamination. Density was measured using a QTRS density scanner. Loblolly pine contained a higher average density. Chemical composition was measured using the NREL standard for identifying the chemical composition of biomass. Southern yellow pine contained a higher % hemicellulose, lignin, and extractives. Douglas-fir had higher % cellulose than southern yellow pine. Surface energy was measured using the static sessile drop contact angle method and the acid/base approach. Southern yellow pine contained a lower average contact angle than Douglas-fir. Shear stress, % wood failure, and durability were measured using ASTM-D2559 with two adhesives, a one-part moisture cure polyurethane (PU), and a two-part ambient curing phenol-resorcinol-formaldehyde (PRF). Shear stress for southern yellow pine was affected the most by the type of growth regions at the bond (juvenile to mature wood) and the assembly times of the adhesives used. Douglas-fir shear stress was affected by the type of adhesive and the growth region at the bond. Delamination results demonstrated that when using PRF the southern yellow pine has less delamination statistically than Douglas-fir. Also, the growth region at the bond with both adhesives showed to impact delamination with juvenile to mature wood having less delamination than mature to mature wood.
Degree
thesis:*- Name thesis:degree_name
- Master of Science
- Level thesis:degree_level
- masters
- Discipline thesis:degree_discipline
- Forest Products
- Department dc:contributor.department
- Forest Resources and Environmental Conservation
- Grantor dc:publisher
- Virginia Tech
- Year dc:date.issued
- 2015
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Mirabile, Kyle Vincent
- Chair dc:contributor.committeechair
-
- Zink-Sharp, Audrey G.
- Committee members dc:contributor.committeemember
-
- Renneckar, Scott Harold
- Frazier, Charles E.
Subjects
dc:subject × 5Rights
dc:rights- Statement dc:rights
-
- In Copyright
- Licence dc:rights.uri
Identifiers
dc:identifier.*- Dc Identifier Other
- vt_gsexam:6460
- OAI identifier oai:identifier
- oai:vtechworks.lib.vt.edu:10919/56970