wood connections - tripod.comacare2.tripod.com/academic/uyg/apa_connections.pdf · key to...
TRANSCRIPT
![Page 1: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/1.jpg)
Wood Connections
Presented by: Karyn Beebe, P.E.
![Page 2: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/2.jpg)
Key to Connections
1. Wood has a strong and weak direction 2. Wood Moves3. Strive for Consistency4. Wood and Moisture Don’t Mix5. Load Path Continuity
![Page 3: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/3.jpg)
Connecting Wood
Wood and compression perpendicular to grainCompare wood cells to a bundle of strawsBundle crushes under perpendicular load
![Page 4: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/4.jpg)
Connecting Wood
Wood and tension perpendicular to grain The evil of wood connections
Initiators:notcheslarge diameter fastenershanging loads
![Page 5: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/5.jpg)
Connecting Wood
Wood likes to take on load spread over its surface
![Page 6: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/6.jpg)
Concentrated at a single fastener –wood is more prone to split and crush
![Page 7: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/7.jpg)
Connection Techniques
Truss platesDesign metal plate connections using the latest edition of ANSI/TPI 1
![Page 8: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/8.jpg)
Connection Techniques
Steel bolts and plates in heavy trusses
![Page 9: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/9.jpg)
Glulam Connections
![Page 10: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/10.jpg)
Field Notching and Drilling of Glued Laminated Timber Beams
Tech Note EWS S560
![Page 11: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/11.jpg)
Possible Reinforcement for an End Notch
Lag screw extends past the neutral axis into the upper portion of beam
Use one or more fully threaded lag screws
Washer Potential crack zone
Neutral axis0.9dminimum
Depth ofnotch = 0.1d
maximum
d
Ref. APA Technical Note EWS S560
![Page 12: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/12.jpg)
![Page 13: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/13.jpg)
Vertical Holes
Strength reduction = 1.5 x Hole diameter/beam width
Example:• 6” Beam width• 1” diameter vertical holeReduction = (1.5 x 1”)/6”Reduction = 0.25Beam is 75% of original strength
Tech Note EWS S560
![Page 14: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/14.jpg)
Hanger to Beam
Load suspended from lower half of beam –another case of tension perpendicular to grain
![Page 15: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/15.jpg)
Hanger to Beam
Load supported in upper half of beam
• Extended plates puts wood in compression when loaded
compression
Full wrap sling option
![Page 16: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/16.jpg)
The Basics - Engineered
Lateral connection strength depends on:
Crushing (bearing) strength of wood
Size of wood pieces
Fastener size and strength
Plus appropriate end use adjustment factors
i.e. Wet service, edge distance, end grain, etc.
![Page 17: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/17.jpg)
The Basics - Engineered
Withdrawal Connection Strength Depends On:
Depth of penetration
Wood density
Fastener size and type
Plus appropriate end use adjustment factors
i.e. wet service, edge distance, end grain, etc.
![Page 18: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/18.jpg)
Connection Techniques
Multi-ply linear members and inter-ply shear/load transfer
![Page 19: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/19.jpg)
Connection Serviceability
Humidity and moisture• Ambient conditions• Contact with cementitious materials
![Page 20: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/20.jpg)
Moisture Changes In Wood
Causes dimensional changes perpendicular to grain
Growing tree is filled with water
As wood dries, it shrinksperp. to grain
![Page 21: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/21.jpg)
Connecting Wood
Wood, like other materials, moves in varying environments
![Page 22: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/22.jpg)
Connection Serviceability
Solid Sawn Glulam
Shrinkage due to moisture loss
![Page 23: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/23.jpg)
Connection Techniques
Gap panels 1/8” to allow for dimensional changes
![Page 24: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/24.jpg)
Beam to Beam
Beam hangersFasteners in top of supported beamWood shrinkageMay splitNot recommended
Split
Gap under beam
![Page 25: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/25.jpg)
![Page 26: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/26.jpg)
Beam to Beam
Beam hangersFasteners in bottom of supported beamWood shrinkage allowedPrevents lateral movement
![Page 27: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/27.jpg)
Beam to Beam
•Concealed– kerf must accommodate steel and weld
– Dowel hole plugged
![Page 28: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/28.jpg)
Beam to Wall
Problem• shrinkage• tension perp
![Page 29: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/29.jpg)
Beam to Wall
Solution:• allows shrinkage
Slotted hardware
![Page 30: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/30.jpg)
Beam to Beam
Weld bracketBucket -styleDapped support beam
![Page 31: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/31.jpg)
Beam to Column
Full-depth side platesMay cause splittingRestrains wood shrinkage
![Page 32: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/32.jpg)
Beam to Column
Smaller side platesTransmit forceAllow wood movement
![Page 33: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/33.jpg)
![Page 34: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/34.jpg)
![Page 35: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/35.jpg)
Before
![Page 36: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/36.jpg)
After
![Page 37: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/37.jpg)
Pre-engineered Connectors
Joist and beam hangers
• Top and face mount• Product specific• Use correct nail• Fill all holes• Ensure proper fastener penetration
![Page 38: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/38.jpg)
![Page 39: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/39.jpg)
Web Stiffener Detail
1/8" Gap>1000lb
>1550 lb
![Page 40: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/40.jpg)
Nails
A few 10d nails –
There are even more!
![Page 41: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/41.jpg)
Nail Nomenclature
There is no control over nail nomenclature!
Manufacturers can and will call fasteners anything that they want.
8d is not a clear specification!
![Page 42: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/42.jpg)
Specifying Nails
Avoid problems by specifying pennyweight, type, diameter and length
Ex: 10d common (0.148” shank dia. X 3” shank length)
![Page 43: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/43.jpg)
Fastener Interchangeability
NER-272 & ESR-1539
Has “conversion” tables for prescriptive requirementsFor example, if model code requires 8d commons at 6” oc, then what fastener type and spacing is “equivalent”
Has values for engineered designs for staples and a variety of other power-driven fasteners
Available from international staple, nail and tool association (ISANTA) www.isanta.org708-482-8138
![Page 44: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/44.jpg)
Shear Walls: Box v. Common
Box v. common nail performanceResearch shows:
Ultimate loads are not significantly affectedStiffness may be reduced about 20%See www.curee.org for woodframe project findingsAPA form TT-087 for more info.
![Page 45: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/45.jpg)
Glued Connections
Adhesive applications
1. Manufactured components
2. Field construction – floors
3. Repair – epoxy*Glued joints are the most unpredictableDifficult to mix glued and mechanical connections
* McGraw-hill handbook of engineered wood construction
![Page 46: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/46.jpg)
Glued Connections
Glued floor construction
Minimize squeaks
Increase stiffness
![Page 47: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/47.jpg)
Glued Connections
Gluing is notrecommended for bonding wall or roof sheathing to framing
![Page 48: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/48.jpg)
Glued Structural Connections
Can be difficult to find design values (i.e. no code reports) for adhesives.
Prohibited (shear walls) in Seismic Design Category D, E, or F (per IBC 2305.3.10)
![Page 49: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/49.jpg)
Power Driven FastenerConsiderations
Contact:
Power driven fasteners rely on velocity to drive fasteners and not mass. They do not have the “clamping” action that the last swing of a hammer provides.
Thin galvanizing - power driven fasteners that are “galvanized” are thinly coated to prevent rusting in the box. The protection is scraped off of the fastener during driving.
Overdriving - if the “gun” is improperly adjusted, overdriven fasteners can be expected. Adjusting air pressure is NOT the correct way to prevent over-driven fasteners.
![Page 50: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/50.jpg)
Mechanical Connections
Nail installationOverdriving reduces performance
![Page 51: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/51.jpg)
Mechanical Connections
Overdriven nails
APA Recommendations – Prescriptive
If < 20% fasteners overdriven by <1/8”, then they may be ignored.
If > 20% fasteners overdriven by >1/8”, then add 1 additional fastener for every 2 overdriven.
![Page 52: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/52.jpg)
Mechanical Connections
Overdriven nails
APA Recommendations – Mechanics Based
If < 20% fasteners overdriven by <1/8”, then they may be ignored.
Otherwise, re-analyze capacity based on average thickness of panel measured from the bottom of the nail head. (i.e. 5/8” panel with fasteners overdriven by 1/8” = capacity of ½” panel.) - Adjust nailing schedule accordingly.
![Page 53: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/53.jpg)
CAUTION!
If the additional nails violate the
minimum spacing requirements
(3” o.c. for 2 inch lumber for splitting),
use staples and ignore the original nails.
![Page 54: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/54.jpg)
Staggered Nailing
Nailing not staggered Nailing staggered
Framing
Wood StructuralPanel
Nail
1/8" GapBetween Panels
Nailing not staggered Nailing staggered
![Page 55: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/55.jpg)
Material Properties of Wood -Problem Areas
Splitting happens because wood is relatively weak perpendicular to grain
Nails too close (act like a wedge)
![Page 56: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/56.jpg)
Material Properties of Wood
Splitting will not occur perpendicular to grain, no matter
how close nails are
Splitting occurs parallel to grain
Staggering
Staggering a line of nails parallel to wood grain minimizes splitting
![Page 57: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/57.jpg)
Material Properties of Wood
Staggered nailing in tightly nailed shear wall helps prevent splitting of framing
![Page 58: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/58.jpg)
Material Properties of Wood Problem Areas
Large plate washers (3”x3”x0.229”), like a 3x sill plate, prevent cross grain bending-
splitting of sill plate (IBC 2305.3.11)Required for SDC D, E or F
Plate washer
Sill plate
Cross grain bending (tension perp. Stresses)
Wood structural panel
![Page 59: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/59.jpg)
Beam to Masonry
•Application• Bearing plate under beam• Prevent contact with
masonry
Capillary break
![Page 60: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/60.jpg)
Beam end bearing on concrete
Notched beam bearingTension perpendicular Differential moisture uptakeReseal end grain
Split
![Page 61: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/61.jpg)
Beam to Masonry
ApplicationNeed 1/2” air gap between wood and masonry
![Page 62: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/62.jpg)
Column to Base
Bearing plateAnchor bolts in bearing plateSlotted column end
Floor slab poured over connection
Can cause decayNot recommended
![Page 63: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/63.jpg)
Column to Base
•Simple steel dowel– Bearing plate
– Shear transfer
![Page 64: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/64.jpg)
Column to Base
•Problem– No weep holes in closed shoe
– Moisture
– Decay
![Page 65: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/65.jpg)
Column to Base
•Where’s the plate?•Grout substituted•Moisture may wick into wood
![Page 66: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/66.jpg)
Connection Serviceability
Issue: Direct water ingressNo weep holes
![Page 67: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/67.jpg)
Arch Base to Support
Good connection• Avoids tension perp• Avoids decay
![Page 68: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/68.jpg)
Connection Serviceability
Issue: direct water ingressWater is absorbed most quickly through wood
end grain
No end caps or flashing
![Page 69: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/69.jpg)
Connection Serviceability
Issue: direct water ingress
Re-direct the water flow around the connection
Preservative treated glulam
end caps and flashing
![Page 70: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/70.jpg)
Continuous Load Path
![Page 71: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/71.jpg)
Connection Techniques
Shear force transfer
Uplift force transfer (New APA Technical Note E510)
![Page 72: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/72.jpg)
Shear Transfer at Engineered Wood Floors, Data File Y250
![Page 73: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/73.jpg)
Connection Techniques
Hold-down hardware
![Page 74: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/74.jpg)
Strap & Shear Inspection
![Page 75: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/75.jpg)
Strap & Shear Inspection
![Page 76: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/76.jpg)
Connection TechniquesHold-Down Placement Traditional
![Page 77: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/77.jpg)
Connection TechniquesHold-Down Placement Perforated
![Page 78: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/78.jpg)
Fasteners and Connections
Prescriptive“follow the recipe” Generally small variables don’t matter. There are no calculations or strength values assigned.
Engineered“do the calculations”All variables are accounted for in calculations
Two design approaches:
![Page 79: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/79.jpg)
Tabulated Values in NDS
The tabulated values for nails, bolts, lag screws and other connectors are nominal and based on certain assumptions.
They must be adjusted to account for actual conditions. Examples:
CD = Load duration factorCM = Wet service factorCg = Group action factorCΔ = Geometry factorCd = Penetration depth factorCtn = Toe-nail factor
![Page 80: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/80.jpg)
Load Duration Factor
Wood capacity greater for short time loading
LOAD DURATION Load Duration Factor - CD
Typical Loads
Permanent 0.9 Dead Load
Ten years 1.0 Floor live load
Two months 1.15 Snow load
Seven days 1.25 Construction load
Ten minutes 1.6 Wind/Earthquake
Impact 2.0 Vehicles
These factors are applied to member capacity
![Page 81: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/81.jpg)
2005 NDS Provisions
Wet Service Factor, CM for connection Z values
Saturated
19% MC
DryCM 1.0 0.7 0.4
Lateral Load
BoltsLag screwsWood screws
fabrication MCin-service MC
![Page 82: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/82.jpg)
Mechanical Connections
Larger fastenersGroup action factor, cg
NDS tablesEquation calculation
![Page 83: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/83.jpg)
Mechanical Connections
![Page 84: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/84.jpg)
Calculated –Group Action Factor, Cg
![Page 85: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/85.jpg)
Tabulated –Group Action Factor, Cg
Am = gross x-sectional area of main member, in2
As = sum of gross x-sectional areas of all side members, in2
![Page 86: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/86.jpg)
Geometry Factor, CΔ
Spacing, End, & Edge DistancesParallel to grain
![Page 87: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/87.jpg)
Local Stresses in Fastener Groups
Net tension:
Row tear-out:
nettNT AFZ '' =
∑=
=
=row
i
i
n
iRTRT
viRT
ZZ
tsFnZ
1
''
min''
Appendix E NDS Expressions
![Page 88: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/88.jpg)
Fastener Penetration, Cd
Lag screws, wood screws, and nails
Fastener Type Full Reduced
Lag Screws 8D 4D
Wood Screws 7D 6D
Nails & Spikes 10D 6D
D = Diameter (in)
![Page 89: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/89.jpg)
Toe-nail Factor, Ctn
Nail installation (11.5.4)Correct toe nailing Fig. 11A5/6 adjustment for lateral2/3 adjustment for withdrawal
![Page 90: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/90.jpg)
"Air Nail" Factor, Cair
Cair= 0.00
![Page 91: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/91.jpg)
Next...
Design software
![Page 92: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/92.jpg)
Eqn’s Easily Solved With a PC
http://www.wwpa.org/_techguide/suite.asp
![Page 93: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/93.jpg)
AWC Connection Calculator
http://www.awc.org/calculators/index.html
![Page 94: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/94.jpg)
Next...
Where to get more information
![Page 95: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/95.jpg)
Where to Find Specifics
IBC, IRC, NDS, ICC-ES
![Page 96: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/96.jpg)
www.awc.orgwww.apawood.orgwww.cwc.cawww.southernpine.com
Web sites...
![Page 97: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/97.jpg)
For More Information: APA Forms
Go to www.apawood.org and enter the Publications store
The following publications expand on the information given in this presentation and can be downloaded for free using subject, title, or form number
![Page 98: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/98.jpg)
APA Forms (www.apawood.org)
T300 – Glulam connection detailsE830 – Screw and plywood connectionsE825 - Bolt and plywood connectionsT325 – Roof fastening for wind upliftY250 – Shear transfer at engineered floorsA410 – Roof retrofit for wind upliftD485 – Corrosion resistant fasteners
![Page 99: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/99.jpg)
APA Forms (www.apawood.org)
TT-035 – Corrosion resistant fastenersTT-036 – Glued floorsTT-039 – Nail withdrawalTT-070 – Nail pull throughTT-045 – Min. nail penetrationTT-012 – Overdriven fastenersTT-056 – Power driven fastenersTT-050/051 – Screw withdrawalTT-058 – Slant nailingTT-061- Nailing thin flange I-joistTT-020 – Dowel bearing strength
![Page 100: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/100.jpg)
www.APACAD.org
![Page 101: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/101.jpg)
www.WoodUniversity.org
![Page 102: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/102.jpg)
Key to Connections
1. Wood has a strong and weak direction 2. Wood Moves3. Strive for Consistency4. Wood and Moisture Don’t Mix5. Load Path Continuity
![Page 103: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/103.jpg)
Quiz: Is the below a code-conforming connection?
![Page 104: Wood Connections - Tripod.comacare2.tripod.com/academic/uyg/APA_Connections.pdf · Key to Connections 1. Wood has a strong and weak direction 2. Wood Moves 3. Strive for Consistency](https://reader037.vdocuments.net/reader037/viewer/2022103106/5a703f347f8b9abb538bc690/html5/thumbnails/104.jpg)
Questions?