CVE 2003C Exam 2 (Wood) UPDATED Actual Exam Questions and CORRECT Answers
0 view 0 purchase
Course
CVE 2003C
Institution
CVE 2003C
CVE 2003C Exam 2 (Wood) UPDATED
Actual Exam Questions and CORRECT
Answers
Endogenous Trees (intertwined growth) - CORRECT ANSWER- very strong and
lightweight trees, not generally used for engineering applications in US
Exogenous (outward growth) - CORRECT ANSWER- Fibers grow from the center...
CVE 2003C Exam 2 (Wood) UPDATED
Actual Exam Questions and CORRECT
Answers
Endogenous Trees (intertwined growth) - CORRECT ANSWER✔✔- very strong and
lightweight trees, not generally used for engineering applications in US
Exogenous (outward growth) - CORRECT ANSWER✔✔- Fibers grow from the center
outward by adding concentric layers (annual rings) which give more predictable engineering
properties in trees
earlywood (light ring) - CORRECT ANSWER✔✔- -structure of wood-
rapid spring growth of hollow thin-walled cells -- spring
latewood (dark ring) - CORRECT ANSWER✔✔- -structure of wood-
dense summer growth of thich-walled cells which are much harder and stronger -- summer
Main structural features of tree stem - CORRECT ANSWER✔✔- from center axis outwards
pith: center stem
heartwood (darker) - provides structural support
sapwood (lighter) - transports the sap
cambium (very thin layer) - location of wood growth
,inner bark
outer bark
Wood is anisotropic (properties change with direction) - CORRECT ANSWER✔✔-
longitudinal - parallel to the long axis (grain), strongest and least shrinkage
radial - perpendicular to the growth rings (out from center)
tangential - tangent to the growth rings, weakest and most shrinkage
**directions influence properties i.e. strength, modulus, thermal expansion, shrinkage, etc.
chemical composition of wood - CORRECT ANSWER✔✔- cellulose (50% by weight,
polymer that forms strands that make up cell walls, Gcellulose=1.5),
lignin (23-33% of softwood, 16-25% of hardwood by weight, glue),
hemicellulose (15-20% of softwood, 20-30% of hardwood),
ash-forming (minerals) (0.1-3% by weight, calcium, potassium, phosphate, silica)
moisture content - CORRECT ANSWER✔✔- shrinkage, strength, and weight depend on
moisture content
depends on air temperature and humidity: slow changing so it tends to adjust near the average
geographic regions
, moisture content = Wm - Wd / Wd x 100
Fiber saturation point (FSP) - CORRECT ANSWER✔✔- moisture content when cells are
completely saturated with bound water but no free water (water inside cell cavities doesnt
affect shrinkage) inside cell cavities
FSP = 21-32%
Above FSP = changes affect only wet weight
Below FSP = small changes strongly affect all physical and mechanical properties
shrinkage - CORRECT ANSWER✔✔- largest shrinkage is in the tangential direction
smallest shrinkage is in the longitudinal direction
zero shrinkage above FSP regardless of direction
assume 6% shrinkage in 30% change in moisture content below FSP (or 1% shrinkage per
5% change in m/c)
wood production steps - CORRECT ANSWER✔✔- Harvesting
Sawing
Seasoning (drying)
Surfacing (Planing)
Grading
Preservative Treating (optional)
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller MGRADES. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $9.49. You're not tied to anything after your purchase.
