Structural Connectors and Their Fasteners

21/10/2011
Agenda
Structural
Connectors and
Their Fasteners
Brent Bunting, P.Eng
•
•
•
•
Introduction to Simpson Strong-Tie
The Building Code
Nails, Wood Screws and Bolts
Limit States Design Catalogue
– General Information
– Installation Guidelines
• Misinstallations
• Corrosion of Connectors With PTW
Who We Are
Humble Beginnings
SST Global
Research and Development
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Literature
www.strongtie.com
Connectors
The Building Code
CSA Standard O86
CSA Standard O86
• 10.10 Joist Hangers
• Sheet steel shall be
hot-dipped galvanized
(10.10.1.3)
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CSA Standard O86
• The hanger shall be
at least half the depth
of the joist unless the
joist is prevented from
twisting by other
means.
CSA Standard O86
• The hanger shall
be fastened to both
the joist and the
header.
(10.10.1.4(b))
(10.10.1.4(a))
• We recommend 60%.
CSA Standard O86
• I-joist hangers that
do not use bearing
stiffeners shall be
high enough to
support the top
flange.
(10.10.1.4(c))
CSA Standard O86
• Where I-joists are
used as the header,
backer blocks shall
be provided
between the web
and the face mount
hanger. (10.10.1.4(d))
• We recommend
backer blocks on
both sides. (APA)
CSA Standard O86
• When an I-joist
supports a top
mount hanger, filler
blocks shall be
used between the
top and bottom
flange of the I-joist.
Blocks shall be tight
to the bottom of the
top flange.
CSA Standard O86
• Testing must be
done in accordance
with ASTM Standard
D1761.
(10.10.1.5)
(10.10.1.4(e))
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Fasteners
The Building Code
• Nails
• 9.23.3.1.(1)
– For all types of connectors
• Wood Screws
– Proprietary
P
i t
screws for
f some connectors
t
– “…nails specified in this section shall be
common steel wire nails or common
spiral
p
nails conforming
g to CSA B111…”
• Bolts
– For special high capacity connections
CSA B111
CSA B111
• Wire Nails, Spikes and
Staples
• Lists 37 different types of nails/spikes
– Table 1 – Common Round Wire Nails
– Table 22 – Common Spiral Nails
– Dimensional information
• Diameter (gauge)
• Length
• Head size
– Table 12 – Round Wire Box Nails
• Gun Nails
– Material requirements
• 90º bend test
CSA B111
Nail Length
(in)
Nail Diameter (in)
Common
Spiral
2½
0.128
0.110
Nail Nomenclature
Box
0.104
3
0.144
0.122
0.116
3¼
0.144
0.122
0.128
3½
0.160
0.152
0.128
• Penny weight system
– 16d nail = 3½” long
– 16 pence for 100 nails
– “d”
d = denarius
• ASTM D1667
– 16d common ≠ 16 box
(0.160” vs. 0.128”)
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Nails
• Shear capacity (lateral) is based on:
– Relative density of the lumber
– Thickness of side member
– Depth of penetration into the header
– Tensile capacity of steel side plate
– Bending strength of the nail
– Cross sectional area of the nail
Effect of Nail Penetration
CSA O86-01
CSA O86-09*
< 8D Penetration = 0%
< 5D Penetration = 0%
8D Penetration = 100%
5D Penetration = 70%
8D Penetration = 84%
12D Penetration = 100%
Penetration
*3” common wire
nail with 14 gauge
steel side plates
D
Effect of Nail Penetration
Effect of Nail Penetration
Effect of Nail Penetration
Effect of Nail Penetration
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Effect of Nail Penetration
Nails
Specialty Short Nails
Nails
• 10d x 1½” nail is NOT a
“Joist Hanger Nail”
• CAN be used when
attaching to a single ply
header at a reduced
capacity
• Same diameter as 10d
common wire nail
Gun Nails
Wood Screws
• ASME Standard B18.6.1
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Wood Screws
Wood Screws
2.6 Material
Wood screws shall be supplied in steel,
corrosion resistant steel
steel, brass
brass, aluminum
alloy, or other materials as designated by
the purchaser. Unless otherwise specified,
no chemical or physical requirements shall
apply.
Proprietary Connector Screws
• Tapered heads will damage
connector holes
SD Structural Connector Screws
• SD Structural Connector screws
– Hex head
•
•
•
•
#9 x 1½
#9 x 2½
#10 x 1½
#10 x 2½
– Approved for use with some connectors
Proprietary Connector Screws
Generic Wood Screws
• Strong Drive Screws (SDS)
– Hex head
– ¼” diameter
– Nine lengths
• Only to be used with
specific connectors
• Also used to laminate
members together
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Bolts
• All bolts are ASTM A307 or
Grade 2.
Bolts
• Carriage bolts are not allowed
– Nut and washer are always
required
– For
F specific
ifi connectors
t
only
l
• Lag Screws are not allowed
Connector Manufacturers
Limit States Design Catalogue
General Notes
General Notes
• CCMC product evaluation reports.
• Load Duration Factors
KD=1.00 – Standard Duration for floors, and
roofs.
KD=1.15 – Short Term for wind and
earthquake only
only.
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General Notes
• Capacities assume Dry Service
Condition (KS=1.00).
General Notes
• Do not bend connectors
in the field unless the
catalogue permits it.
• Other service conditions may
mean a reduction in capacity.
• Wet service condition means a
reduction of 1/3rd in capacity for
nail or screw connections (i.e.
• Connectors that can be
bent in the field can only
be bent once.
multiply table value by 0.67).
General Notes
• Built up members must be fastened
together to act as one unit.
General Notes
• Not all LVL is the same
• Load transfer between plies is not done by
the hanger.
General Notes
Connector Holes
• Always install the
correct quantity,
type and size of
fastener specified
in the catalogue.
• We always specify
common wire
nails.
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General Installation Information
Top Flange Hangers
Hanger Rotation
Joist Connection
Joist Connection
IUS / ITS
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Wood Nailers
Wood Nailers
Wood Nailers
LSSU - Field Adjustable
Misinstallations
Misinstallations
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Misinstallations
Misinstallations
Misinstallations
Misinstallations
Misinstallations
Misinstallations
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Misinstallations
Misinstallations
Misinstallations
Misinstallations
Misinstallations
Misinstallations
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Misinstallations
Corrosion
Corrosion
Corrosion
As of December 31,
2003 CCA is mainly
restricted to below
grade applications.
• The two main alternative chemicals in
Canada are:
– Alkaline Copper Quat (ACQ-C, ACQ-D)
– Copper Azole (CBA-A, CA-B)
As a result, the Wood
Preservatives industry
must use alternative
chemicals to treat
wood.
• Each has substantially more copper (Cu) in
its formulation than CCA.
Corrosion
• Copper + Zinc + moisture = Bad
Corrosion
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Corrosion
• Always compare
recommendation
from treated wood
supplier, chemical
manufacturer and
component
manufacturer and
use most
conservative
suggestion.
Corrosion
• Do NOT use aluminum with preservative
treated woods.
Corrosion
• Do NOT mix metals.
• For galvanized connectors use galvanized
fasteners.
• For stainless steel connectors use
stainless steel fasteners.
THANK YOU
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