structural connectors and their fasteners 3 csa standard o86 • the hanger shall be at least half...
TRANSCRIPT
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Structural Connectors and Their Fasteners
Brent Bunting, P.Eng
Agenda
• Introduction to Simpson Strong-Tie• The Building Code• Nails, Wood Screws and Bolts• Limit States Design Catalogue• 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
• 10.10 Joist Hangers
CSA Standard O86
• 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.(10.10.1.4(a))
• We recommend 60%.
CSA Standard O86
• The hanger shall be fastened to boththe joist and the header.(10.10.1.4(b))
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 webbetween 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 theused between the top and bottom flange of the I-joist. Blocks shall be tight to the bottom of the top flange.(10.10.1.4(e))
CSA Standard O86
• Testing must be done in accordance with ASTM Standard D1761.(10.10.1.5)
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Fasteners
• Nails– For all types of connectors
• Wood ScrewsP i t f t– Proprietary screws for some connectors
• Bolts– For special high capacity connections
The Building Code
• 9.23.3.1.(1)– “…nails specified in this section shall be
common steel wire nails or common spiral nails conforming to CSA B111…”p g
CSA B111
• Wire Nails, Spikes and Staples– Dimensional information
• Diameter (gauge)• Diameter (gauge)• Length• Head size
– Material requirements• 90º bend test
CSA B111
• Lists 37 different types of nails/spikes– Table 1 – Common Round Wire Nails– Table 22 – Common Spiral Nails
– Table 12 – Round Wire Box Nails• Gun Nails
CSA B111
Nail Length(in)
Nail Diameter (in)Common Spiral Box
2½ 0.128 0.110 0.1043 0.144 0.122 0.116
3¼ 0.144 0.122 0.1283½ 0.160 0.152 0.128
Nail Nomenclature
• Penny weight system– 16d nail = 3½” long– 16 pence for 100 nails
“d” = denarius– 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– 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%8D Penetration = 100%
< 5D Penetration = 0%5D Penetration = 70%8D Penetration = 84%
Penetration
D
12D Penetration = 100%
*3” common wire nail with 14 gauge steel side plates
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
• 10d x 1½” nail is NOT a “Joist Hanger Nail”
• CAN be used when attaching to a single plyattaching to a single ply header at a reduced capacity
• Same diameter as 10d common wire nail
Nails
Gun Nails Wood Screws
• ASME Standard B18.6.1
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Wood Screws
2.6 Material
Wood screws shall be supplied in steel, corrosion resistant steel brass aluminumcorrosion resistant steel, brass, aluminum alloy, or other materials as designated by the purchaser. Unless otherwise specified, no chemical or physical requirements shall apply.
Wood Screws
• Tapered heads will damage connector holes
Proprietary Connector Screws
• SD Structural Connector screws– Hex head
• #9 x 1½• #9 x 2½#9 x 2½• #10 x 1½• #10 x 2½
– Approved for use with some connectors
SD Structural Connector Screws
Proprietary Connector Screws
• Strong Drive Screws (SDS)– Hex head– ¼” diameter
Nine lengths– Nine lengths• Only to be used with
specific connectors• Also used to laminate
members together
Generic Wood Screws
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Bolts
• All bolts are ASTM A307 or Grade 2.– Nut and washer are always
requiredF ifi t l– For specific connectors only
Bolts
• Carriage bolts are not allowed
• Lag Screws are not allowed
Connector Manufacturers Limit States Design Catalogue
• CCMC product evaluation reports.
General Notes General Notes
• Load Duration FactorsKD=1.00 – Standard Duration for floors, and
roofs.KD=1.15 – Short Term for wind and
earthquake onlyearthquake only.
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General Notes
• Capacities assume Dry Service Condition (KS=1.00).
• 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. multiply table value by 0.67).
General Notes
• Do not bend connectors in the field unless the catalogue permits it.
• Connectors that can be bent in the field can only be bent once.
General Notes
• Built up members must be fastened together to act as one unit.
• Load transfer between plies is not done by the hanger.
General Notes
• Not all LVL is the same
General Notes
• Always install the correct quantity, type and size of fastener specified in the catalogue.
• We always specify common wire nails.
Connector Holes
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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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MisinstallationsCorrosion
As of December 31, 2003 CCA is mainly restricted to below grade applications.
Corrosion
As a result, the Wood Preservatives industry must use alternative chemicals to treat wood.
• The two main alternative chemicals in Canada are:– Alkaline Copper Quat (ACQ-C, ACQ-D)– Copper Azole (CBA-A, CA-B)
Corrosion
• Each has substantially more copper (Cu) in its formulation than CCA.
• Copper + Zinc + moisture = Bad
Corrosion 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 mix metals.
• For galvanized connectors use galvanized fasteners.fasteners.
• For stainless steel connectors use stainless steel fasteners.
• Do NOT use aluminum with preservative treated woods.
Corrosion THANK YOU