Structural elements calculators
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Wood Fastener Capacity Calculator

Jonathan Ochshorn


Directions: Enter values for type of fastener (bolt, lag screw, or nail); fastener dimensions; number of shear planes (single or double, with double only available for bolted connections); adjustments (duration of load, CD, and wet service factor, CM); material and section properties for main and side member(s); and fastener spacing, edge and end distances (not required for nails).

Press "update" button.

The unadjusted and adjusted capacity for a single fastener and for the entire connection are calculated, based on "yield limit" theory (per NDS 2005). Only the capacity based on the fasteners themselves is computed: neither the wood elements themselves, nor any steel side plates specified, are checked for strength or serviceability. Spacing, edge, and end distances for fasteners are checked for bolts and lag screws in wood members, with the capacity adjusted accordingly. Such spacing and edge/end distances are not checked for steel side plates.

More detailed explanations and examples can be found in my text.