c wsf 2012 showalter connections

8/12/2019 C WSF 2012 Showalter Connections

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Connection Solutions for

Wood-frame Structures

Presented by:

John Buddy Showalter, P.E.

Vice President, Technology Transfer

The Wood Products Councilis a Registered Provider with . Credit(s) earned on completion of this program will be reportedto AIA/CESfor AIA members. Certificates of Completion for both AIA

members and non-AIA members are available upon request. This program is registered with AIA/CESfor continuing professional

education. As such, it does not include content that may be deemedor 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 beaddressed at the conclusion of this presentation.

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 isprohibited.

American Wood Council 2012

Learning ObjectivesAt the end of this program, participants will be knowledgeable of:

1. Identify basic wood material properties and learn how to

avoid splits, notching, and checking in connection

solutions.

2. Recommend fastening guidelines for wood-to-steel,wood-to-concrete, and wood-to-wood connections.

3. Describe effects of moisture on wood connections andimplement proper flashing to avoid problems.

4. Identify proper fastener selection in size, scope, andpattern.


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initiators:

notches large diameter fasteners hanging loads

Split


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Load

Displacement

high strength, poor ductilitygood strength, good ductility

low strength, good ductility


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No end caps or flashing

end caps and flashing

Moisture trap -

No weep holes


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Saturated

19% MC

Dry

CM 1.0 0.7 0.4*

Lateral load (*CM=0.7 for D1/4)

fabrication MCin-service MC

CM= 1.0 if:

1 fastener

2+ fasteners

split spliceplates


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Slotted hardware


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Need 1/2air gap between

wood and masonry


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www.tfguild.org

www.timberframe.org

Schmidt, R.J. (2006): Timber Pegs Considerations for Mortise and Tenon

Joint Design, Structure Magazine, March 2006, NCSEA, 13(3):44-47.

Fastener Values

Included in U.S. design literatureFastener Type Reference

Bolts NDS or NER

Lag Screws NDS or NER

Wood Screws NDS or NER

Nails & Spikes NDS or NER

Split Ring Connectors NDS

Shear Plate Connectors NDS

Drift Bolts & Drift Pins NDS

Metal Plate Connectors NER

Hangers & Framing Anchors NER

Staples NER

National Evaluation

Reports (NER) are

developed for

proprietary products


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Center-Point Bending TestLoad

6 Yield ModesSingle & double shearWood-to-woodWood-to-SteelWood-to-Concrete

I

II

III

IV


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Nail Types and Designations

Nail types described in Appendix LNail Types and Designations

Nail capacity tables in 2005 NDS

NDS 11.3.4 The length of dowel bearing shall notinclude the length of the tapered tip of a fastener for

fastener penetration lengths less than 10D.


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l l

shearplane

Dr

use D

r

shear plane

Because the induced

maximum moment canoccur in the threadsif

the shear planeis not

located sufficiently into

the shank away from thethreads


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Group Action Factor, Cg

Equation method

where:

( )( )[ ]

+

+++

=

m

R

mmmRn

mmC EA

nn

EA

n

g1

1

111

)1(2

2

ss

mm

mm

ss

EA

AE

AE

AE

AER oroflessorthe=

1

2

= uum

++=

ssmm AEAE

su

11

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Group Action Factor, Cg

Group Action Factor , Cg

Not applicable here- loads acting along the

length of the member are unit loads

Anc hor Bol ts and

Washers as requiredBottom Plate


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Appendix ENDS Expressions

Group tear-out

Note: spacing between outer rowsof fasteners paralleling the member

on a single splice plate < 5

netgrouptbottomRTtopRT

GT AFZZ

Z

++= '''

'

22


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Hidden kerf plates


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Connectionsdesign

software


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