Bolt head and washer bearing capacity in a wood member (tension).
Bolt head and washer bearing capacity in a wood member (tension).
(OP)
This idea was brought up by DaveAtkins in this thread: thread507-22707: Uplift Capacity of Sill Plate Anchor Bolts.
I have a configuration in a wood wind frame that will cause direct tension to act on a bolt (see attached file). NDS lists perpendicular bearing capacities for So. Pine at 565 psi. However, in the Dowel-Type Fasteners Chapter, the capacity for dowels in shear (same general mechanical force orientation) for perpendicular to grain between 2550-5150 psi, based on their diameter. There is nearly an order of magnitude difference.
I equate the difference to block shear rupture strength in steel. Can anyone give NDS reference or theoretical concept for design basis?
I have a configuration in a wood wind frame that will cause direct tension to act on a bolt (see attached file). NDS lists perpendicular bearing capacities for So. Pine at 565 psi. However, in the Dowel-Type Fasteners Chapter, the capacity for dowels in shear (same general mechanical force orientation) for perpendicular to grain between 2550-5150 psi, based on their diameter. There is nearly an order of magnitude difference.
I equate the difference to block shear rupture strength in steel. Can anyone give NDS reference or theoretical concept for design basis?






RE: Bolt head and washer bearing capacity in a wood member (tension).
Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.
RE: Bolt head and washer bearing capacity in a wood member (tension).
RE: Bolt head and washer bearing capacity in a wood member (tension).
Thanks Woodman88
RE: Bolt head and washer bearing capacity in a wood member (tension).
RE: Bolt head and washer bearing capacity in a wood member (tension).
RE: Bolt head and washer bearing capacity in a wood member (tension).
A wood dowel doesn't behave that way (in part because a wood dowel will have a lengthwise (axial) grain structure) and the wood structural members will be perpendicular to that grain in one o=r the other holes. A wood dowel, under almost all reasonable construction techniques, will be driven firmly into the hole between both wood structural members, and (usually) wedged tight. Further wetting/drying tightens a dowel joint, rather than loosening as in a steel-through-wood-hole joint.