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3/18/2013
1
WoodWorks
• Archie Landreman, CSI
Design and Proper Use of Engineered Wood
Beams
Copyright Materials
This presentation is protected by US and International Copyright laws. Reproduction,
distribution, display and use of the presentation without written permission of the speaker is
prohibited.
© The Wood Products Council 2012
“The Wood Products Council” is a Registered Provider with The American Institute of Architects Continuing Education Systems (AIA/CES). Credit(s) earned on completion of this program will be reported to AIA/CES for AIA members. Certificates of Completion for both AIA members and non-AIA members are available upon request. This program is registered with AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.
Objectives
Acquire working knowledge of Engineered Wood Beams
Differentiate Engineered Wood Beams Based on availability, cost, and strength
Evaluate the use of Engineered Wood Beams for a variety of applications
Identify how Engineered Wood Beams are commonly used based on project examples
What is an Engineered Wood Product?
Any wood-based building material that has been improved physically by a manufacturing process.
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Engineered Wood Products
Designed by optimally orienting wood strands, veneers or laminations
Using structural durable adhesives Forming larger composite products With engineered properties manufactured to maximize wood’s natural and strength characteristics
Engineered Wood Products
Environmentally Friendly
LVL-Laminated Veneer Lumber LSL-Laminated Strand Lumber PSL-Parallel Strand Lumber
Laminated Veneer Lumber (LVL)
Veneers bonded together Beams, headers, rafters &
scaffold planking Common thicknesses: ¾” to 3-1/2”
All grain parallel to length
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Laminated Veneer Lumber = LVL
• Readily and widely available • Variety of stress classes available to suit specific designs • Competitively priced • Strength achieved not by densification, but by grading and
optimum layup of veneers • To reduce handling of heavy beams, LVL can be site built into
wider beams by nailing or bolting • Dimensionally stable, water repellent sealers available to
extend exposure performance • Typical applications: beams, headers, columns, joists, studs,
ridge beams, truss chords, scaffold planking, and I-joist flanges
LVL Beams in I-Joist Floor Systems
LVL Floor Beam Side Loaded Side Loaded LVL
Timberstrand LSL
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Solid Start LSL Laminated Strand Lumber = LSL
• Permits use of smaller, variable quality logs • Higher shear strength than LVL & PSL • Allows holes 2x larger than LVL or PSL • Typically less expensive than LVL & PSL • Can be the best value, if structural demands are met • Excellent fastener holding strength • Species include aspen, yellow poplar • Commonly used for headers, beams, columns,
studs, stair stringers, door & window parts
Parallam® PSL introduced 1988
PSL means: Parallel
Strand Lumber Parallam® is a registered
trademark brand name of iLevel.
Parallam® Exterior Solutions
Parallel Strand Lumber = PSL
•Stronger & stiffer than LSL •Generally more $ than LVL, LSL, or Glulam •Allows higher fiber utilization than LVL •Readily treated with preservatives •Easily bolted •Used for columns, header, beams, trusses. •For interior apps-can be finished & left exposed
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WOOD SOLUTIONS FAIR December 7, 2011
Today’s Glulam – Important Considerations for Design and Construction Professionals Tom Williamson, P.E.
Consulting Engineer Retired Vice President, APA Past Executive VP, AITC
What is Glulam?
Glulam = a structural composite of lumber and adhesives
Glulam
Wood laminations bonded together
Wood grain runs parallel to the length
Typical Widths: 2-1/2" to 10-3/4"
Laminations: 1-3/8" for Southern Pine 1-1/2" for Douglas Fir
Dispersal of Strength Reducing Characteristics
Single Lamination
Glued Laminated Timber
Glulam – One of the Original Glued Engineered Wood Composites
Introduced in the U.S. in 1933 Over 115 years
of use worldwide
1933 – First Glulam in the U.S.A. Madison, WI
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Spans of 100 feet or greater Oceans Exhibit – Indianapolis Zoo
10-3/4” x 72” 115 ft. clear span
Unmatched Versatility of Shapes and Spans Glulam Lay-Ups
302-24 T.L. No. 1 No. 2
No. 2 No. 1
302-24 T.L.
No. 3
Balanced
No. 2D No. 2 No. 2
No. 2 No. 1
302-24 T.L.
No. 3
Unbalanced
Tension Zone Inner Zone Tension Zone
Compression Zone Inner Zone Tension Zone
Member Type
Column
Simple span beam
Truss member
Cantilever span beam
E-Rated Southern Pine Layup 30F – 2.1E Stress Grade
2.3E
No. 1D No. 2D
No. 2D No. 1D
2.3E
No. 2M Limited to nominal 6 inch width or less
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SYP 2.1 E LVL Hybrid Glulam with LVL Outer Laminations
Full length with no finger joints required
LVL has greater tensile strength compared to lumber
30F-2.1E stress level achieved
Direct substitute for many SCL products
LVL Laminations
FRP Reinforced Glulam
Fiberglass Carbon Kevlar Other
Fiber Reinforced Polymers (FRP)
Thin Layer of FRP
Western Washington University
Small Gym 12-1/4” x 70” x 78 ft. 10-3/4” x 57” x 78 ft.
Natatorium 12-1/4” x 81” x 91 ft. 10-3/4” x 64-1/2” x 91 ft.
Western Washington University
Main Gym 14-1/4” x 90” x 106 ft. 10-3/4” x 75” x 106 ft.
Cost savings for the FRP glulam beams was $22,000
Product Basics Large Cross Sections Are Possible
21” x 27” x 110’ Note multiple pieces positioned side by side
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Note the “TOP” Stamp for Unbalanced Layup
Unbalanced Layups “Upside Down” Bending Stresses
Based on full-size beam tests conducted at APA, the “upside down” bending stress is 75% of the normal bending capacity
Specifying Camber
Glulam can be manufactured with camber to offset the anticipated dead load deflection Very important for long span members
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Beam Orientation and Sizes
• Horizontal or load perpendicular to face
• Typical beam depths
• 9” – 30”
• Typical beam widths
• 3-1/8” and 3-1/2”
• 5-1/8” and 5-1/2”
• 6-3/4”
Stock Glulam Sizes
width
depth
• Lengths are available as needed from distribution yards
• Typical IJC beam depths
• 9-1/2”, 11-7/8”
• 14” and 16”
• Widths for IJC beams match 2x4 and 2x6 framing
Stock Glulam IJC Sizes
Question and answers
82
Naturally Durable Species
Port Orford Cedar 22F-1.8E Alaska Yellow Cedar 20F-1.5E Western Red Cedar 16F-1.3E California Redwood 16F-1.1E
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Alaska Yellow Cedar (AYC) Santa Monica, CA Reservoir Cover
Preservative Treatment of Glulam
Untreated glulam in pressure cylinder ready for treatment
Preservative forced into wood cells under pressure
See APA Technical Note S580
Characteristics of Glulam in Fire
Wood is an excellent heat insulator
Develops a char layer after fire exposure
Self-extinguishing after fire source removed
Retains significant residual strength after being exposed to fire
10-3/4 x 16-1/2
Glulam: Char
Glulam: Fire Resistance
Fire Protection
Tension Lam Provisions
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Chemical Storage Facility Portland, OR
Twin Rink Ice Arena Anaheim, CA.
2010 Olympic Skating Oval Richmond, B.C.
Cathedral of Light – Oakland, CA
Toronto Ontario Art Gallery
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Glulam Truss Bridge in Hiroshima Japan
Total length = 650 ft. Main central span = 275 ft. Tower height = 155 ft. Truss depth = 10 ft.
Stress Classes Combined for Simplicity
Selecting and Sizing Floor Beam Assumptions Dry Use Uniform Load Only – No Point Loads Beam Weight Included Most Restrictive of Simple or Multiple Span Conditions Live Load = 80% of Total Load Load Duration Factor = 1.00 Live Load Deflection = L/360 Total Load Deflection = L/240 Adequate Bearing Area Provided Continuous Lateral Bracing Along Top and Bottom Chords
and at Top and Bottom at Ends of Beam
Beam Comparisons-Floor Beam A Beam Type
MOE (psi)
Fb (psi)
Span (ft)
Width (in)
Depth (in)
Total Load (plf)
Actual Cap. (plf)
Pass Horiz. Shear (psi)
LSL 1.55 2325 8 3.5 9.5 1200 1292 310
LSL 1.75 2500 “ “ “ “ 1406 410
LVL 1.5 2250 “ “ “ “ 1150 No 220
LVL 1.9 2600 “ “ “ “ 1462 285
LVL 2.0 2900 “ “ “ “ 1493 285
LVL 2.0 3100 “ “ “ “ 1493 285
PSL 2.0 2900 “ “ “ “ 1517 290
GL SP 2.1 3000 “ “ “ “ 1645 300
GL DF 1.8 2400 “ “ 9.0 “ 1174 No 265
GL DF 1.8 2400 “ “ 10.5 “ 1599
Floor Beam 8-0-0
Span in Feet: 8-0-0 Total Load: 1200# Beam Width: 3.5” Beam Depth: 9.5” Beam Type: LSL 1.55E 2325fb Actual Capacity: 1292# Note: 310fv
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Floor Beam 8-0-0
Span in Feet: 8-0-0 Total Load: 1200# Beam Width: 3.5” Beam Depth: 9.5” Beam Type: LSL 1.75E 2500fb Actual Capacity: 1406# Note: 410fv
Floor Beam 8-0-0
Span in Feet: 8-0-0 Total Load: 1200# Beam Width: 3.5” Beam Depth: 9.5” Beam Type: LVL 1.5E 2250fb Actual Capacity: 1150# Fails Note: 220fv
Floor Beam 8-0-0
Span in Feet: 8-0-0 Total Load: 1200# Beam Width: 3.5” Beam Depth: 9.5” Beam Type: LVL 1.9E 2600fb Actual Capacity: 1462# Note: 285fv
Floor Beam 8-0-0
Span in Feet: 8-0-0 Total Load: 1200# Beam Width: 3.5” Beam Depth: 9.5” Beam Type: LVL 2.0E 2900fb Actual Capacity: 1493# Note: 285fv
Floor Beam 8-0-0
Span in Feet: 8-0-0 Total Load: 1200# Beam Width: 3.5” Beam Depth: 9.5” Beam Type: LVL 2.0E 3100fb Actual Capacity: 1493# Note: 285fv
Floor Beam 8-0-0
Span in Feet: 8-0-0 Total Load: 1200# Beam Width: 3.5” Beam Depth: 9.0” Beam Type: DF Glulam 1.8E 2400fb Actual Capacity: 1174# Fails Note: 265fv Note: 3.5”x10.5” Supports 1599#
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Floor Beam 8-0-0
Span in Feet: 8-0-0 Total Load: 1200# Beam Width: 3.5” Beam Depth: 9.5” Beam Type: PSL 2.0E 2900fb Actual Capacity: 1517# Note: 290fv
Floor Beam 8-0-0
Span in Feet: 8-0-0 Total Load: 1200# Beam Width: 3.5” Beam Depth: 9.5” Beam Type: SYP Glulam 2.1E 3000fb Actual Capacity: 1645# Note: 300fv
Beam Comparisons-Floor Beam C Beam Type
MOE (psi)
Fb (psi)
Span (ft)
Width (in)
Depth (in)
Total Load (plf)
Actual Cap. (plf)
Pass Horiz. Shear (psi)
LSL 1.55 2325 20 3.5 14 300 312 310
LVL 1.5 2250 “ “ “ “ 321 220
LSL 1.75 2500 “ “ “ “ 352 410
LVL 1.7 2400 “ “ “ “ 362 285
LVL 1.9 2600 “ “ “ “ 387 285
LVL 2.0 2900 “ “ “ “ 432 285
LVL 2.0 3100 “ “ “ “ ---- ----
PSL 2.0 2900 “ “ “ “ 407 290
GL DF 2.1 3000 “ “ “ “ 455 300
GL DF 1.8 2400 “ “ 13.5 “ 288 No 265
GL DF 1.8 2400 “ “ 15 “ 397
Floor Beam 20-0-0
Span in Feet: 20-0-0 Total Load: 300# Beam Width: 3.5” Beam Depth: 14” Beam Type: LSL 1.55E 2325fb Actual Capacity: 312# Note: 310fv
Floor Beam 20-0-0
Span in Feet: 20-0-0 Total Load: 300# Beam Width: 3.5” Beam Depth: 14” Beam Type: LVL 1.5E 2250fb Actual Capacity: 321# Note: 220fv
Floor Beam 20-0-0
Span in Feet: 20-0-0 Total Load: 300# Beam Width: 3.5” Beam Depth: 14” Beam Type: LSL 1.75E 2500fb Actual Capacity: 352# Note: 410fv
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Floor Beam 20-0-0
Span in Feet: 20-0-0 Total Load: 300# Beam Width: 3.5” Beam Depth: 14” Beam Type: LVL 1.7E 2400fb Actual Capacity: 362# Note: 285fv
Floor Beam 20-0-0
Span in Feet: 20-0-0 Total Load: 300# Beam Width: 3.5” Beam Depth: 14” Beam Type: LVL 1.9E 2600fb Actual Capacity: 387# Note: 285fv
Floor Beam 20-0-0
Span in Feet: 20-0-0 Total Load: 300# Beam Width: 3.5” Beam Depth: 14” Beam Type: LVL 2.0E 2900fb Actual Capacity: 432# Note: 285fv
Floor Beam 20-0-0
Span in Feet: 20-0-0 Total Load: 300# Beam Width: 3.5” Beam Depth: 13.5” Beam Type: DF Glulam 1.8E 2400fb Actual Capacity: 288# Fails Note: 265fv Use 3.5” x 15” = 397# T.L.
Floor Beam 20-0-0
Span in Feet: 20-0-0 Total Load: 300# Beam Width: 3.5” Beam Depth: 14” Beam Type: PSL 2.0E 2900fb Actual Capacity: 407# Note: 290fv
Floor Beam 20-0-0
Span in Feet: 20-0-0 Total Load: 300# Beam Width: 3.5” Beam Depth: 14” Beam Type: DF Glulam 2.1E 3000fb Actual Capacity: 455# Note: 300fv
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LVL Conclusions
Ability to Nail in Place Most Commonly Available Engineered Wood
Beam Various Grades Available in Wide Widths (Verify) Competitive Pricing Available as Studs and Columns
LSL Conclusions
Best for Short Spans Large Holes Capability One Piece Solution Headers in Walls Available as Columns and Studs Tall Wall Applications
PSL Conclusions
High Strength Available in Wide Widths Can be Treated Can be Used in Timber Type Trusses Can be Exposed and Stained/Painted Available as Columns
Glulam Conclusions
Architectural Grades Available High Strength Hybrid Beams Widest Widths Available Can be Cambered and Curved Some Beams are Individually Wrapped Deepest Depths Available Cost Competitive with SCL Available in DF, SYP, Cedar and Others Can be Treated
Glulam Design References
AITC “Timber Construction Manual”
McGraw-Hill “APA Engineered Wood Construction Guide”
McGraw-Hill “Wood Engineering and Construction Handbook”
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Questions? • This concludes The American
Institute of Architects Continuing Education Systems Course
Archie Landreman, CSI WoodWorks [email protected]
Thank You
Archie Landreman, CSI [email protected]
262-497-5550 www.woodworks.org