21/10/2011. 1. Structural. Connectors and. Their Fasteners. Brent Bunting, P.Eng.
Agenda. • Introduction to Simpson Strong-Tie. • The Building Code. • Nails ...
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
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.
• 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.
