medium_span_wood Flashcards
(20 cards)
What are the main advantages of using wood as a construction material?
Beauty, ease of use, familiarity, and general availability
What are common imperfections in wood that affect its structural performance?
Knots, twisting, splitting, grain directionality, moisture-related movement
Why is it difficult to use solid wood for medium spans?
Long, straight, defect-free trees are hard to find; structural limits of natural wood
What structural element mimics steel I-beams in wood construction?
I-joists
What are the components of an I-joist?
Top and bottom wood chords with a plywood web in between
What span ranges can I-joists typically handle?
Up to 30–35 feet
What is the primary structural function of the chords in an I-joist?
Top chord resists compression, bottom chord resists tension
What type of wood product is LVL and how is it made?
Laminated Veneer Lumber; thick plywood-like beam made of glued, layered wood veneers
What are typical LVL depths for medium span applications?
Around 12–16 inches
Why are LVLs advantageous in beam applications?
High strength, predictable performance, easy to screw/nail into, consistent shape
What are Parallams made from?
Smaller wood strands glued and pressed into large structural members
What distinguishes glulams from LVLs and Parallams?
Made from full dimensional lumber pieces glued together; often used for exposed applications
Why are glulams typically used in visible design elements?
They are visually attractive, with clean finishes and customizable shapes
How can glulams accommodate long spans?
Built from small wood pieces into large members; can span 30–60+ feet
What is camber in glulam beams?
An intentional upward curve built in to counteract deflection under load
What are wood trusses in medium span systems made from?
Top and bottom chords with web members, typically made from 2x lumber
How are wood trusses connected?
With pressed metal connector plates (nailing plates)
What span ranges can wood trusses typically handle?
20 to 40 feet
What is a key advantage of wood trusses over solid joists?
Open webs allow for easy routing of ducts and utilities
What are the relative costs of engineered wood products?
Glulams are most expensive, followed by LVLs/Parallams, then I-joists
