Dowel Bearing Strength

Dowel bearing strength (Fe)is the property of wood that affects the nominal design value for a single fastener subjected to lateral shear load (Z).  It is associated with the crushing strength of a wood member under loading from a dowel.  The dowel bearing strength of a member depends on the relative size of the dowel and the specific gravity of wood.  The angle of load to grain also affects the dowel bearing strength for large-diameter fasteners. 

The tests in this module were performed on yellow poplar (YP) spedimens, YP laminated veneer lumber (LVL), and YP-based oriented strand lumber (OSL)using ASTM Standard D5764 (1998) - half hole specimen configuration.  The specimen is rectangular with a half-hole drilled in the width face, which is used to evaluate the resistance to embedding the dowel in the hole without bending the fastener.  The localized crushing strength of the wood (Fe) under the dowel is used in conjunction with dowel bending strength to determine connection design values. 

The dowel bearing test was conducted on the four specimens pictured below, using a 1/2" diameter bolt.  This module allows you to view a direct comparison of two specimens at once.  There is also a tutorial to show you how to determine the 5% D offset load. 

 

YP t.GIF (852 bytes)

y13a.jpg (20398 bytes) YPPERP.jpg (4611 bytes)

Yellow Poplar loaded perpendicular to grain

YP II

y9b.jpg (19414 bytes) YPPARL.jpg (4384 bytes)

Yellow Poplar loaded parallel to grain

LVL t.GIF (852 bytes)

LVL.jpg (5110 bytes) t11a.jpg (23034 bytes)

Laminated veneer lumber (LVL) loaded perpendicular to grain

OSL II

k196a.jpg (21887 bytes) OSL.jpg (5146 bytes)

Oriented strand lumber (OSL) loaded parallel to grain

 

To view the dowel bearing tests click on the comparisons in the left hand frame.
You will need Windows Media Player 6 or newer version to view tests.
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Note that the videos of dowel bearing tests work best on Internet Explorer

 

The development of this on-line tutorial was supported by The American Forest and Paper Association.  Web site designed and created by Frank Godina, Aaron Henson, Ken Fridley, and Dave Pollock.

If you have any difficulties accessing, downloading, and/or otherwise using this site to its fullest, please contact Dave Pollock